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Added new examples for 1D single phase flows
authormichael <michael@localhost.localdomain>
Sat, 12 Dec 2020 12:32:07 +0000 (13:32 +0100)
committermichael <michael@localhost.localdomain>
Sat, 12 Dec 2020 12:32:07 +0000 (13:32 +0100)
CDMATH/tests/examples/CMakeLists.txt
CDMATH/tests/examples/EulerSystem1D/EulerSystem1DConservativeStaggered/CMakeLists.txt [new file with mode: 0755]
CDMATH/tests/examples/EulerSystem1D/EulerSystem1DConservativeStaggered/EulerSystem1DConservativeStaggered.py [new file with mode: 0644]
CDMATH/tests/examples/EulerSystem1D/EulerSystem1DUpwind/CMakeLists.txt [new file with mode: 0755]
CDMATH/tests/examples/EulerSystem1D/EulerSystem1DUpwind/EulerSystem1DUpwind.py [new file with mode: 0644]
CDMATH/tests/examples/EulerSystem1D/EulerSystem1DUpwindEntrCorr/CMakeLists.txt [new file with mode: 0755]
CDMATH/tests/examples/EulerSystem1D/EulerSystem1DUpwindEntrCorr/EulerSystem1DUpwindEntrCorr.py [new file with mode: 0644]
CDMATH/tests/examples/EulerSystem_Shock/EulerSystemStaggered/CMakeLists.txt [new file with mode: 0755]
CDMATH/tests/examples/EulerSystem_Shock/EulerSystemStaggered/EulerIsothermal_2DConservativeStaggered.py [new file with mode: 0644]

index 7bb78e6c65e9b80f0c14a5dab38858b8511b78fa..8543fb9460a7e29aa76fcd3cd628b1af55d9cffb 100755 (executable)
@@ -9,6 +9,7 @@ file(GLOB NICE_EXAMPLES_TO_INSTALL
   WaveSystem1DUpwind WaveSystem1DUpwind_RiemannProblem WaveSystem1Staggered_RiemannProblem WaveSystem2DUpwind_RiemannProblem
 WaveSystem_Stationary/WaveSystemUpwind WaveSystem_Stationary/WaveSystemCentered WaveSystem_Stationary/WaveSystemPStag WaveSystem_Stationary/WaveSystemStaggered 
 WaveSystem_Shock/WaveSystemUpwind WaveSystem_Shock/WaveSystemCentered WaveSystem_Shock/WaveSystemPStag WaveSystem_Shock/WaveSystemStaggered 
+EulerSystem1D/EulerSystem1DUpwind EulerSystem1D/EulerSystem1DUpwindEntrCorr EulerSystem1D/EulerSystem1DConservativeStaggered EulerSystem_Shock/EulerSystemStaggered EulerSystem_Shock/EulerSystemUpwind
 )
 
 install(DIRECTORY ${NICE_EXAMPLES_TO_INSTALL} DESTINATION share/examples)
@@ -54,7 +55,11 @@ IF (CDMATH_WITH_PYTHON AND CDMATH_WITH_PETSC AND CDMATH_WITH_POSTPRO)
     ADD_SUBDIRECTORY(WaveSystem_Shock/WaveSystemPStag)
     ADD_SUBDIRECTORY(WaveSystem_Shock/WaveSystemStaggered)
     ADD_SUBDIRECTORY(WaveSystem_Shock/WaveSystemCentered)
+    ADD_SUBDIRECTORY(EulerSystem1D/EulerSystem1DUpwind)
+    ADD_SUBDIRECTORY(EulerSystem1D/EulerSystem1DUpwindEntrCorr)
+    ADD_SUBDIRECTORY(EulerSystem1D/EulerSystem1DConservativeStaggered)
     ADD_SUBDIRECTORY(EulerSystem_Shock/EulerSystemUpwind)
+    ADD_SUBDIRECTORY(EulerSystem_Shock/EulerSystemStaggered)
 ENDIF (CDMATH_WITH_PYTHON AND CDMATH_WITH_PETSC AND CDMATH_WITH_POSTPRO)
 
 
diff --git a/CDMATH/tests/examples/EulerSystem1D/EulerSystem1DConservativeStaggered/CMakeLists.txt b/CDMATH/tests/examples/EulerSystem1D/EulerSystem1DConservativeStaggered/CMakeLists.txt
new file mode 100755 (executable)
index 0000000..a4899a3
--- /dev/null
@@ -0,0 +1,8 @@
+
+if (CDMATH_WITH_PYTHON AND CDMATH_WITH_PETSC AND CDMATH_WITH_POSTPRO)
+
+    ADD_TEST(ExampleEulerSystem_1DShock_ConservativeStaggered ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/EulerSystem1DConservativeStaggered.py )
+
+endif (CDMATH_WITH_PYTHON AND CDMATH_WITH_PETSC AND CDMATH_WITH_POSTPRO)
+
+
diff --git a/CDMATH/tests/examples/EulerSystem1D/EulerSystem1DConservativeStaggered/EulerSystem1DConservativeStaggered.py b/CDMATH/tests/examples/EulerSystem1D/EulerSystem1DConservativeStaggered/EulerSystem1DConservativeStaggered.py
new file mode 100644 (file)
index 0000000..c1158ac
--- /dev/null
@@ -0,0 +1,291 @@
+#!/usr/bin/env python3
+# -*-coding:utf-8 -*
+
+# Isothermal Euler system
+# d rho/d t + d q/d x =0
+# d q/d t + d (q^2/rho+p)/d x = 0, where q = rho*u and p = c^2*rho
+# UU = (rho,q) : conservative variable
+# Scheme : Conservative stagerred scheme (Ait Ameur et al)
+# Author :  Katia Ait Ameur
+# Date : November 2020
+
+import cdmath
+import numpy as np
+import matplotlib
+matplotlib.use("Agg")
+import matplotlib.pyplot as plt
+import matplotlib.animation as manimation
+from math import sqrt
+
+c0=330.#reference sound speed for water at 15 bars
+precision=1e-5
+rho0=1
+
+def initial_conditions_Riemann_problem(a,b,nx):
+    print("Initial data Riemann problem")
+    dx = (b - a) / nx #space step
+    x=[a+0.5*dx + i*dx for i in range(nx)]   # array of cell center (1D mesh)
+    rho_initial = [ (xi<(a+b)/2)*rho0        + (xi>=(a+b)/2)*rho0*2       for xi in x]
+    q_initial   = [ (xi<(a+b)/2)*rho0*(-300) + (xi>=(a+b)/2)*rho0*2*(-300)  for xi in x]
+
+    return rho_initial, q_initial
+
+def matrix_coef(rho_l,q_l,rho_r,q_r):
+    m_coef = -0.5*(q_l-q_r)/rho_r
+    return m_coef
+
+def jacobianMatricesm(coeff,rho_l,q_l,rho_r,q_r):
+    RoeMat   = cdmath.Matrix(2,2);
+    Dmac     = cdmath.Matrix(2,2);   
+    
+    u_l=q_l/rho_l  
+    u_r=q_r/rho_r
+    Dmac_coef = matrix_coef(rho_l,q_l,rho_r,q_r)
+    if rho_l<0 or rho_r<0 :
+        print( "rho_l=",rho_l, " rho_r= ",rho_r)
+        raise ValueError("Negative density")
+    u = (u_l*sqrt(rho_l)+u_r*sqrt(rho_r))/(sqrt(rho_l)+sqrt(rho_r));   
+    RoeMat[0,0]   = 0
+    RoeMat[0,1]   = 1
+    RoeMat[1,0]   = c0*c0 - u*u
+    RoeMat[1,1]   = 2*u
+    
+    Dmac[0,0]= abs(u)-u;
+    Dmac[0,1]= 1;
+    Dmac[1,0]= -c0*c0-u*u;
+    Dmac[1,1]= abs(u)+u; 
+
+    return (RoeMat-Dmac)*coeff*0.5
+def jacobianMatricesp(coeff,rho_l,q_l,rho_r,q_r):
+    RoeMat   = cdmath.Matrix(2,2);
+    Dmac = cdmath.Matrix(2,2);   
+    
+    u_l=q_l/rho_l 
+    u_r=q_r/rho_r
+    Dmac_coef = matrix_coef(rho_l,q_l,rho_r,q_r)
+    if rho_l<0 or rho_r<0 :
+        print( "rho_l=",rho_l, " rho_r= ",rho_r)
+        raise ValueError("Negative density")
+    u = (u_l*sqrt(rho_l)+u_r*sqrt(rho_r))/(sqrt(rho_l)+sqrt(rho_r));   
+    RoeMat[0,0]   = 0
+    RoeMat[0,1]   = 1
+    RoeMat[1,0]   = c0*c0 - u*u
+    RoeMat[1,1]   = 2*u
+    
+    Dmac[0,0]= abs(u)-u;
+    Dmac[0,1]= 1;
+    Dmac[1,0]= -c0*c0-u*u;
+    Dmac[1,1]= abs(u)+u; 
+
+    return (RoeMat+Dmac)*coeff*0.5
+
+def EulerSystemStaggered(ntmax, tmax, cfl, a,b,nx, output_freq, meshName):
+    dim=1
+    nbComp=dim+1
+    nbCells = nx
+    dt = 0.
+    dx=(b-a)/nx
+    dt = cfl * dx / c0
+    nbVoisinsMax=2
+
+    time = 0.
+    it=0;
+    iterGMRESMax=50
+    newton_max = 50
+    isStationary=False
+
+    #iteration vectors
+    Un =cdmath.Vector(nbCells*(dim+1))
+    dUn=cdmath.Vector(nbCells*(dim+1))
+    dUk=cdmath.Vector(nbCells*(dim+1))
+    Rhs=cdmath.Vector(nbCells*(dim+1))
+
+    # Initial conditions #
+    print("Construction of the initial condition …")
+    rho_field, q_field = initial_conditions_Riemann_problem(a,b,nx)
+    v_field   = [   q_field[i]/rho_field[i]  for i in range(nx)]
+    p_field   = [ rho_field[i]*(c0*c0)       for i in range(nx)]
+
+    max_initial_rho=max(rho_field)
+    min_initial_rho=min(rho_field)
+    max_initial_q=max(q_field)
+    min_initial_q=min(q_field)
+    max_initial_p=max(p_field)
+    min_initial_p=min(p_field)
+    max_initial_v=max(v_field)
+    min_initial_v=min(v_field)
+
+    for k in range(nbCells):
+        Un[k*nbComp+0] = rho_field[k]
+        Un[k*nbComp+1] =   q_field[k]
+
+    print("Starting computation of the non linear Euler system with staggered scheme …")
+    divMat=cdmath.SparseMatrixPetsc(nbCells*nbComp,nbCells*nbComp,(nbVoisinsMax+1)*nbComp)
+
+    # Picture settings
+    fig, ([axDensity, axMomentum],[axVelocity, axPressure]) = plt.subplots(2, 2,sharex=True, figsize=(10,10))
+    fig.suptitle('Conservative staggered scheme')
+    lineDensity, = axDensity.plot([a+0.5*dx + i*dx for i in range(nx)], rho_field, label='Density') #new picture for video # Returns a tuple of line objects, thus the comma
+    axDensity.set(xlabel='x (m)', ylabel='Density')
+    axDensity.set_xlim(a,b)
+    axDensity.set_ylim(min_initial_rho - 0.1*(max_initial_rho-min_initial_rho), max_initial_rho +  0.1*(max_initial_rho-min_initial_rho) )
+    axDensity.legend()
+    lineMomentum, = axMomentum.plot([a+0.5*dx + i*dx for i in range(nx)], q_field, label='Momentum')
+    axMomentum.set(xlabel='x (m)', ylabel='Momentum')
+    axMomentum.set_xlim(a,b)
+    axMomentum.set_ylim(min_initial_q - 0.1*(max_initial_q-min_initial_q), max_initial_q +  0.1*(max_initial_q-min_initial_q) )
+    axMomentum.legend()
+    lineVelocity, = axVelocity.plot([a+0.5*dx + i*dx for i in range(nx)], v_field, label='Velocity')
+    axVelocity.set(xlabel='x (m)', ylabel='Velocity')
+    axVelocity.set_xlim(a,b)
+    axVelocity.set_ylim(min_initial_v - 0.4*abs(min_initial_v), max_initial_v +  0.05*abs(max_initial_v) )
+    axVelocity.legend()
+    linePressure, = axPressure.plot([a+0.5*dx + i*dx for i in range(nx)], p_field, label='Pressure')
+    axPressure.set(xlabel='x (m)', ylabel='Pressure')
+    axPressure.set_xlim(a,b)
+    axPressure.set_ylim(min_initial_p - 0.05*abs(min_initial_p), max_initial_p +  0.05*abs(max_initial_p) )
+    axPressure.ticklabel_format(axis='y', style='sci', scilimits=(0,0))
+    axPressure.legend()
+    # Video settings
+    FFMpegWriter = manimation.writers['ffmpeg']
+    metadata = dict(title="Conservative staggered scheme for the 1D isothermal Euler System", artist = "CEA Saclay", comment="Shock tube")
+    writer=FFMpegWriter(fps=10, metadata=metadata, codec='h264')
+    with writer.saving(fig, "1DEuler_System_ConservativeStaggered"+".mp4", ntmax):
+        writer.grab_frame()
+        plt.savefig("EulerSystem"+str(dim)+"D_ConservativeStaggered"+meshName+"_0"+".png")
+
+        # Starting time loop
+        while (it<ntmax and time <= tmax and not isStationary):
+            dUn = Un.deepCopy()
+            Uk  = Un.deepCopy()
+            residu = 1.
+            k=0
+            while (k<newton_max and residu > precision ):
+                #DEBUT BOUCLE NEWTON
+                divMat.zeroEntries()#sets the matrix coefficients to zero
+                for j in range(nbCells):# 
+                    if ( j==0) : 
+                        rho_r = Uk[j*nbComp+0]
+                        q_r   = Uk[j*nbComp+1]
+                        rho_l = rho_r # Conditions de Neumann
+                        q_l   =   q_r
+                        Am= jacobianMatricesm(dt/dx,rho_l,q_l,rho_r,q_r)
+                        divMat.addValue(j*nbComp,(j+1)*nbComp,Am)
+                        divMat.addValue(j*nbComp,    j*nbComp,Am*(-1.))
+                        dUi=cdmath.Vector(2)
+                        dUi[0] = Uk[(j+1)*nbComp+0]-Uk[j*nbComp+0]
+                        dUi[1] = Uk[(j+1)*nbComp+1]-Uk[j*nbComp+1]
+                        temp=cdmath.Vector(2)
+                        temp = Am*dUi
+                        #print("Bloc 0 matrix  :   ", Am)
+                        Rhs[j*nbComp+0] = -temp[0]-(Uk[j*nbComp+0]-Un[j*nbComp+0]) 
+                        Rhs[j*nbComp+1] = -temp[1]-(Uk[j*nbComp+1]-Un[j*nbComp+1]) 
+                    elif ( j==nbCells-1) :
+                        rho_l = Uk[j*nbComp+0]
+                        q_l   = Uk[j*nbComp+1]
+                        rho_r = rho_l # Conditions de Neumann
+                        q_r   =   q_l
+                        Ap= jacobianMatricesp(dt/dx,rho_l,q_l,rho_r,q_r)
+                        divMat.addValue(j*nbComp,    j*nbComp,Ap)
+                        divMat.addValue(j*nbComp,(j-1)*nbComp,Ap*(-1.))
+                        dUi=cdmath.Vector(2)
+                        dUi[0] = Uk[(j-1)*nbComp+0]-Uk[j*nbComp+0]
+                        dUi[1] = Uk[(j-1)*nbComp+1]-Uk[j*nbComp+1]
+                        temp=cdmath.Vector(2)
+                        temp = Ap*dUi
+                        Rhs[j*nbComp+0] = temp[0]-(Uk[j*nbComp+0]-Un[j*nbComp+0]) 
+                        Rhs[j*nbComp+1] = temp[1]-(Uk[j*nbComp+1]-Un[j*nbComp+1]) 
+                    else :
+                        rho_l = Uk[(j-1)*nbComp+0]
+                        q_l   = Uk[(j-1)*nbComp+1]
+                        rho_r = Uk[j*nbComp+0]
+                        q_r   = Uk[j*nbComp+1]
+                        Ap = jacobianMatricesp(dt/dx,rho_l,q_l,rho_r,q_r)
+                        ###############################################################
+                        rho_l = Uk[j*nbComp+0]
+                        q_l   = Uk[j*nbComp+1]
+                        rho_r = Uk[(j+1)*nbComp+0]
+                        q_r   = Uk[(j+1)*nbComp+1]
+                        Am = jacobianMatricesm(dt/dx,rho_l,q_l,rho_r,q_r)
+                        divMat.addValue(j*nbComp,(j+1)*nbComp,Am)
+                        divMat.addValue(j*nbComp,    j*nbComp,Am*(-1.))
+                        divMat.addValue(j*nbComp,    j*nbComp,Ap)
+                        divMat.addValue(j*nbComp,(j-1)*nbComp,Ap*(-1.))
+                        dUi1=cdmath.Vector(2)
+                        dUi2=cdmath.Vector(2)
+                        dUi1[0] = Uk[(j+1)*nbComp+0]-Uk[j*nbComp+0]
+                        dUi1[1] = Uk[(j+1)*nbComp+1]-Uk[j*nbComp+1]
+                        dUi2[0] = Uk[(j-1)*nbComp+0]-Uk[j*nbComp+0]
+                        dUi2[1] = Uk[(j-1)*nbComp+1]-Uk[j*nbComp+1] 
+                        temp1 = cdmath.Vector(2)
+                        temp2 = cdmath.Vector(2)
+                        temp1 = Am*dUi1
+                        temp2 = Ap*dUi2
+                        Rhs[j*nbComp+0] = -temp1[0] + temp2[0] -(Uk[j*nbComp+0]-Un[j*nbComp+0]) 
+                        Rhs[j*nbComp+1] = -temp1[1] + temp2[1] -(Uk[j*nbComp+1]-Un[j*nbComp+1]) 
+                divMat.diagonalShift(1)#only after  filling all coefficients
+                LS=cdmath.LinearSolver(divMat,Rhs,iterGMRESMax, precision, "GMRES","LU")
+                dUk=LS.solve(); 
+                residu = dUk.norm()
+                #stop
+                Uk+=dUk
+                if(not LS.getStatus()):
+                    print("Linear system did not converge ", LS.getNumberOfIter(), " GMRES iterations")
+                    raise ValueError("Pas de convergence du système linéaire");
+                k=k+1
+            Un = Uk.deepCopy()
+            dUn-=Un
+            for k in range(nbCells):
+                rho_field[k] = Un[k*(dim+1)+0]
+                q_field[k]   = Un[k*(dim+1)+1] 
+            v_field   = [   q_field[i]/rho_field[i]  for i in range(nx)]
+            p_field   = [ rho_field[i]*(c0*c0)       for i in range(nx)]
+
+            lineDensity.set_ydata(rho_field)
+            lineMomentum.set_ydata(q_field)
+            lineVelocity.set_ydata(v_field)
+            linePressure.set_ydata(p_field)
+            writer.grab_frame()
+
+            time=time+dt;
+            it=it+1;
+            #Sauvegardes
+            if(it==1 or it%output_freq==0 or it>=ntmax or isStationary or time >=tmax):
+                print("-- Iter: " + str(it) + ", Time: " + str(time) + ", dt: " + str(dt))
+                #print("Last linear system converged in ", LS.getNumberOfIter(), " GMRES iterations", ", residu final:   ",residu)
+
+                plt.savefig("EulerSystem"+str(dim)+"D_ConservativeStaggered"+meshName+"_"+str(it)+".png")
+                print
+    print("-- Iter: " + str(it) + ", Time: " + str(time) + ", dt: " + str(dt))
+    if(it>=ntmax):
+        print("Nombre de pas de temps maximum ntmax= ", ntmax, " atteint")
+        return
+    elif(isStationary):
+        print("Régime stationnaire atteint au pas de temps ", it, ", t= ", time)
+        print("------------------------------------------------------------------------------------")
+        plt.savefig("EulerSystem"+str(dim)+"Staggered"+meshName+"_Stat.png")
+        return
+    else:
+        print("Temps maximum Tmax= ", tmax, " atteint")
+        return
+
+def solve( a,b,nx, meshName, meshType, cfl):
+    print("Resolution of the Euler system in dimension 1 on "+str(nx)+ " cells")
+    print("Initial data : ", "Riemann problem")
+    print("Boundary conditions : ", "Neumann")
+    print("Mesh name : ",meshName , ", ", nx, " cells")
+    # Problem data
+    tmax = 10.
+    ntmax = 50
+    output_freq = 10
+    EulerSystemStaggered(ntmax, tmax, cfl, a,b,nx, output_freq, meshName)
+    return
+
+if __name__ == """__main__""":
+    a=0.
+    b=1.
+    nx=100
+    cfl=0.99
+    solve( a,b,nx,"SquareRegularSquares","RegularSquares",cfl)
diff --git a/CDMATH/tests/examples/EulerSystem1D/EulerSystem1DUpwind/CMakeLists.txt b/CDMATH/tests/examples/EulerSystem1D/EulerSystem1DUpwind/CMakeLists.txt
new file mode 100755 (executable)
index 0000000..8b41b92
--- /dev/null
@@ -0,0 +1,8 @@
+
+if (CDMATH_WITH_PYTHON AND CDMATH_WITH_PETSC AND CDMATH_WITH_POSTPRO)
+
+    ADD_TEST(ExampleEulerSystem_1DShock_UpwindExplicit ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/EulerSystem1DUpwind.py )
+
+endif (CDMATH_WITH_PYTHON AND CDMATH_WITH_PETSC AND CDMATH_WITH_POSTPRO)
+
+
diff --git a/CDMATH/tests/examples/EulerSystem1D/EulerSystem1DUpwind/EulerSystem1DUpwind.py b/CDMATH/tests/examples/EulerSystem1D/EulerSystem1DUpwind/EulerSystem1DUpwind.py
new file mode 100644 (file)
index 0000000..ee66cd1
--- /dev/null
@@ -0,0 +1,199 @@
+# Isothermal Euler system
+# d rho/d t + d q/d x =0
+# d q/d t + d (q^2/rho+p)/d x = 0, where q = rho*u and p = c^2*rho
+# UU = (rho,q) : conservative variable
+# Scheme : Roe scheme (without any entropy correction)
+# Comment : the solution displays a non entropic (non physical) shock instead of a rarefaction wave
+# Date : November 2020
+
+from cdmath import *
+import numpy as np
+from math import sqrt
+
+import matplotlib
+matplotlib.use("Agg")
+import matplotlib.pyplot as plt
+import matplotlib.animation as manimation
+
+c0=330.#reference sound speed for water at 15 bars
+precision=1e-5
+
+def flux(rho,q):
+    fl = Vector(2);
+    fl[0] = q;
+    fl[1] = q*q/rho + c0*c0*rho;    
+    return fl
+
+def compTimeStep(UU,dx,CFL):
+    M = UU.getMesh();
+    maxAbsEigVa = 0;
+    for i in range(M.getNumberOfCells()):
+        maxAbsEigVa = max(maxAbsEigVa,abs(UU[i,1]/UU[i,0]+c0),abs(UU[i,1]/UU[i,0]-c0));
+        pass
+    dt = CFL*dx/maxAbsEigVa;
+    return dt
+
+def AbsRoeMatrix(rho_l,q_l,rho_r,q_r):
+    AbsRoeMa = Matrix(2,2);
+    u_l = q_l/rho_l;
+    u_r = q_r/rho_r;
+    u = (u_l*sqrt(rho_l)+u_r*sqrt(rho_r))/(sqrt(rho_l)+sqrt(rho_r));   
+    AbsRoeMa[0,0]=(abs(u-c0)*(u+c0)+abs(u+c0)*(c0-u))/(2*c0);
+    AbsRoeMa[0,1]= (abs(u+c0)-abs(u-c0))/(2*c0);
+    AbsRoeMa[1,0]=(abs(u-c0)*(u*u-c0*c0)+abs(u+c0)*(c0*c0-u*u))/(2*c0);
+    AbsRoeMa[1,1]=((u+c0)*abs(u+c0)-(u-c0)*abs(u-c0))/(2*c0);
+    return AbsRoeMa;
+    
+def main(meshName):
+    # mesh definition    
+    xmin=.0;
+    xmax= 1;
+    nx=100#1000;
+    ntmax=50;
+    dx = (xmax-xmin)/nx;
+    M=Mesh(xmin,xmax,nx);
+    dim=1
+    
+    # initial time
+    time=0.;
+    # maximum time T
+    tmax=0.01;
+    it=0;
+    freqSortie=10;
+    # CFL condition
+    CFL=0.99;
+    # conservative variable (unknown)
+    UU=Field("Conservative variables",CELLS,M,2);
+
+    # initial condition for Riemann problem
+    print("Construction of the initial condition …")
+    rhoL=1
+    vL=-300
+    rhoR=1.45
+    vR=-300
+    for i in range(M.getNumberOfCells()):
+        x=M.getCell(i).x();
+        if x < (xmax-xmin)/2:
+            UU[i,0] = rhoL;
+            UU[i,1] = rhoL*vL;
+        else:
+            UU[i,0] = rhoR;
+            UU[i,1] = rhoR*vR;
+        pass
+
+    rho_field = [ UU[i,0]          for i in range(nx)]
+    q_field   = [ UU[i,1]          for i in range(nx)]
+    v_field   = [ UU[i,1]/UU[i,0]  for i in range(nx)]
+    p_field   = [ UU[i,0]*(c0*c0)  for i in range(nx)]
+
+    max_initial_rho=max(rhoL,rhoR)
+    min_initial_rho=min(rhoL,rhoR)
+    max_initial_p=max_initial_rho*c0*c0
+    min_initial_p=min_initial_rho*c0*c0
+    max_initial_v=max(vL,vR)
+    min_initial_v=min(vL,vR)
+    max_initial_q=max(vL*rhoL,vR*rhoR)
+    min_initial_q=min(vL*rhoL,vR*rhoR)
+
+    print( "Numerical solution of the 1D Euler equation")
+
+    # prepare some memory
+    UU_limL = Vector(2);
+    UU_limR = Vector(2);
+    Del_UU_RL = Vector(2);
+    UU_new = UU;
+    
+    # Picture settings
+    fig, ([axDensity, axMomentum],[axVelocity, axPressure]) = plt.subplots(2, 2,sharex=True, figsize=(10,10))
+    fig.suptitle('Explicit Upwind scheme')
+    lineDensity, = axDensity.plot([xmin+0.5*dx + i*dx for i in range(nx)], rho_field, label='Density') #new picture for video # Returns a tuple of line objects, thus the comma
+    axDensity.set(xlabel='x (m)', ylabel='Density')
+    axDensity.set_xlim(xmin,xmax)
+    axDensity.set_ylim(min_initial_rho - 0.1*(max_initial_rho-min_initial_rho), max_initial_rho +  0.1*(max_initial_rho-min_initial_rho) )
+    axDensity.legend()
+    lineMomentum, = axMomentum.plot([xmin+0.5*dx + i*dx for i in range(nx)], q_field, label='Momentum')
+    axMomentum.set(xlabel='x (m)', ylabel='Momentum')
+    axMomentum.set_xlim(xmin,xmax)
+    axMomentum.set_ylim(min_initial_q - 0.1*(max_initial_q-min_initial_q), max_initial_q +  0.1*(max_initial_q-min_initial_q) )
+    axMomentum.legend()
+    lineVelocity, = axVelocity.plot([xmin+0.5*dx + i*dx for i in range(nx)], v_field, label='Velocity')
+    axVelocity.set(xlabel='x (m)', ylabel='Velocity')
+    axVelocity.set_xlim(xmin,xmax)
+    axVelocity.set_ylim(min_initial_v - 0.25*abs(min_initial_v), max_initial_v +  0.05*abs(max_initial_v) )
+    axVelocity.legend()
+    linePressure, = axPressure.plot([xmin+0.5*dx + i*dx for i in range(nx)], p_field, label='Pressure')
+    axPressure.set(xlabel='x (m)', ylabel='Pressure')
+    axPressure.set_xlim(xmin,xmax)
+    axPressure.set_ylim(min_initial_p - 0.05*abs(min_initial_p), max_initial_p +  0.05*abs(max_initial_p) )
+    axPressure.ticklabel_format(axis='y', style='sci', scilimits=(0,0))
+    axPressure.legend()
+    # Video settings
+    FFMpegWriter = manimation.writers['ffmpeg']
+    metadata = dict(title="Upwind (Roe) scheme for the 1D isothermal Euler System", artist = "CEA Saclay", comment="Shock tube")
+    writer=FFMpegWriter(fps=10, metadata=metadata, codec='h264')
+    with writer.saving(fig, "1DEuler_System_Upwind"+".mp4", ntmax):
+        writer.grab_frame()
+        plt.savefig("EulerSystem"+str(dim)+"UpwindExplicit"+meshName+"_0"+".png")
+
+        # loop in time
+        while (it<ntmax and time <= tmax ):
+            # time step
+            dt=compTimeStep(UU,dx,CFL);
+            # Neumann boundary condition
+            UU_limL[0] = UU[0,0];
+            UU_limL[1] = UU[0,1];
+            UU_limR[0] = UU[M.getNumberOfCells()-1,0];
+            UU_limR[1] = UU[M.getNumberOfCells()-1,1];
+            flux_iminus = flux(UU_limL[0],UU_limL[1]);
+            #Main loop on cells
+            for i in range(0,M.getNumberOfCells()):
+                if (i<M.getNumberOfCells()-1):
+                    Del_UU_RL[0]=UU[i+1,0]-UU[i,0];
+                    Del_UU_RL[1]=UU[i+1,1]-UU[i,1];
+                    AbsRoeMa = AbsRoeMatrix(UU[i,0],UU[i,1],UU[i+1,0],UU[i+1,1]);
+                    flux_iplus = (flux(UU[i,0],UU[i,1])+flux(UU[i+1,0],UU[i+1,1]))-AbsRoeMa*Del_UU_RL;
+                    flux_iplus[0]*=0.5;
+                    flux_iplus[1]*=0.5;
+                else:
+                    flux_iplus= flux(UU_limR[0],UU_limR[1]);
+                UU_new[i,0] = UU[i,0] - dt/dx*(flux_iplus[0]-flux_iminus[0]);
+                UU_new[i,1] = UU[i,1] - dt/dx*(flux_iplus[1]-flux_iminus[1]);
+                flux_iminus = flux_iplus;
+                pass
+            UU = UU_new;
+            time+=dt;
+            it+=1;
+
+            rho_field = [ UU[i,0]  for i in range(nx)]
+            q_field   = [ UU[i,1]  for i in range(nx)]
+            v_field   = [ UU[i,1]/UU[i,0]  for i in range(nx)]
+            p_field   = [ UU[i,0]*(c0*c0)  for i in range(nx)]
+
+            lineDensity.set_ydata(rho_field)
+            lineMomentum.set_ydata(q_field)
+            lineVelocity.set_ydata(v_field)
+            linePressure.set_ydata(p_field)
+            writer.grab_frame()
+
+            if (it%freqSortie==0):
+                print( "-- Iter : ", it," Time : ",time," dt : ",dt)
+                plt.savefig("EulerSystem"+str(dim)+"UpwindExplicit"+meshName+"_"+str(it)+".png")
+            pass
+
+    print("-- Iter: " + str(it) + ", Time: " + str(time) + ", dt: " + str(dt))
+    if(it>=ntmax):
+        print("Nombre de pas de temps maximum ntmax= ", ntmax, " atteint")
+        return
+    elif(isStationary):
+        print("Régime stationnaire atteint au pas de temps ", it, ", t= ", time)
+        print("------------------------------------------------------------------------------------")
+        plt.savefig("EulerSystem"+str(dim)+"UpwindExplicit"+meshName+"_Stat.png")
+        return
+    else:
+        print("Temps maximum Tmax= ", tmax, " atteint")
+
+    return
+
+if __name__ == '__main__':
+    main("SquareRegularSquares")
diff --git a/CDMATH/tests/examples/EulerSystem1D/EulerSystem1DUpwindEntrCorr/CMakeLists.txt b/CDMATH/tests/examples/EulerSystem1D/EulerSystem1DUpwindEntrCorr/CMakeLists.txt
new file mode 100755 (executable)
index 0000000..655c40f
--- /dev/null
@@ -0,0 +1,8 @@
+
+if (CDMATH_WITH_PYTHON AND CDMATH_WITH_PETSC AND CDMATH_WITH_POSTPRO)
+
+    ADD_TEST(ExampleEulerSystem_1DShock_UpwindExplicit_EntrCorr ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/EulerSystem1DUpwindEntrCorr.py )
+
+endif (CDMATH_WITH_PYTHON AND CDMATH_WITH_PETSC AND CDMATH_WITH_POSTPRO)
+
+
diff --git a/CDMATH/tests/examples/EulerSystem1D/EulerSystem1DUpwindEntrCorr/EulerSystem1DUpwindEntrCorr.py b/CDMATH/tests/examples/EulerSystem1D/EulerSystem1DUpwindEntrCorr/EulerSystem1DUpwindEntrCorr.py
new file mode 100644 (file)
index 0000000..e1ae7f0
--- /dev/null
@@ -0,0 +1,199 @@
+# Isothermal Euler system
+# d rho/d t + d q/d x =0
+# d q/d t + d (q^2/rho+p)/d x = 0, where q = rho*u and p = c^2*rho
+# UU = (rho,q) : conservative variable
+# Scheme : Roe scheme with entropy correction 
+# Comment : If one removes the entropic correction the result displays a non entropic (non physical) shock instead of a rarefaction wave
+# Date : November 2020
+
+from cdmath import *
+import numpy as np
+from math import sqrt
+
+import matplotlib
+matplotlib.use("Agg")
+import matplotlib.pyplot as plt
+import matplotlib.animation as manimation
+
+c0=330.#reference sound speed for water at 15 bars
+precision=1e-5
+
+def flux(rho,q):
+    fl = Vector(2);
+    fl[0] = q;
+    fl[1] = q*q/rho + c0*c0*rho;    
+    return fl
+
+def compTimeStep(UU,dx,CFL):
+    M = UU.getMesh();
+    maxAbsEigVa = 0;
+    for i in range(M.getNumberOfCells()):
+        maxAbsEigVa = max(maxAbsEigVa,abs(UU[i,1]/UU[i,0]+c0),abs(UU[i,1]/UU[i,0]-c0));
+        pass
+    dt = CFL*dx/maxAbsEigVa;
+    return dt
+
+def AbsRoeMatrix(rho_l,q_l,rho_r,q_r):
+    AbsRoeMa = Matrix(2,2);
+    u_l = q_l/rho_l;
+    u_r = q_r/rho_r;
+    u = (u_l*sqrt(rho_l)+u_r*sqrt(rho_r))/(sqrt(rho_l)+sqrt(rho_r));   
+    AbsRoeMa[0,0]=(abs(u-c0)*(u+c0)+abs(u+c0)*(c0-u))/(2*c0);
+    AbsRoeMa[0,1]= (abs(u+c0)-abs(u-c0))/(2*c0);
+    AbsRoeMa[1,0]=(abs(u-c0)*(u*u-c0*c0)+abs(u+c0)*(c0*c0-u*u))/(2*c0);
+    AbsRoeMa[1,1]=((u+c0)*abs(u+c0)-(u-c0)*abs(u-c0))/(2*c0);
+    return AbsRoeMa;
+    
+def main(meshName):
+    # mesh definition    
+    xmin=.0;
+    xmax= 1;
+    nx=200#1000;
+    ntmax=100;
+    dx = (xmax-xmin)/nx;
+    M=Mesh(xmin,xmax,nx);
+    dim=1
+    
+    # initial time
+    time=0.;
+    # maximum time T
+    tmax=0.01;
+    it=0;
+    freqSortie=10;
+    # CFL condition
+    CFL=0.9;
+    # conservative variable (unknown)
+    UU=Field("Conservative variables",CELLS,M,2);
+
+    # initial condition for Riemann problem
+    print("Construction of the initial condition …")
+    rhoL=1
+    vL=-300
+    rhoR=2
+    vR=-300
+    for i in range(M.getNumberOfCells()):
+        x=M.getCell(i).x();
+        if x < (xmax-xmin)/2:
+            UU[i,0] = rhoL;
+            UU[i,1] = rhoL*vL;
+        else:
+            UU[i,0] = rhoR;
+            UU[i,1] = rhoR*vR;
+        pass
+
+    rho_field = [ UU[i,0]          for i in range(nx)]
+    q_field   = [ UU[i,1]          for i in range(nx)]
+    v_field   = [ UU[i,1]/UU[i,0]  for i in range(nx)]
+    p_field   = [ UU[i,0]*(c0*c0)  for i in range(nx)]
+
+    max_initial_rho=max(rhoL,rhoR)
+    min_initial_rho=min(rhoL,rhoR)
+    max_initial_p=max_initial_rho*c0*c0
+    min_initial_p=min_initial_rho*c0*c0
+    max_initial_v=max(vL,vR)
+    min_initial_v=min(vL,vR)
+    max_initial_q=max(vL*rhoL,vR*rhoR)
+    min_initial_q=min(vL*rhoL,vR*rhoR)
+
+    print( "Numerical solution of the 1D Euler equation")
+
+    # prepare some memory
+    UU_limL = Vector(2);
+    UU_limR = Vector(2);
+    Del_UU_RL = Vector(2);
+    UU_new = UU;
+    
+    # Picture settings
+    fig, ([axDensity, axMomentum],[axVelocity, axPressure]) = plt.subplots(2, 2,sharex=True, figsize=(10,10))
+    fig.suptitle('Explicit Upwind scheme')
+    lineDensity, = axDensity.plot([xmin+0.5*dx + i*dx for i in range(nx)], rho_field, label='Density') #new picture for video # Returns a tuple of line objects, thus the comma
+    axDensity.set(xlabel='x (m)', ylabel='Density')
+    axDensity.set_xlim(xmin,xmax)
+    axDensity.set_ylim(min_initial_rho - 0.1*(max_initial_rho-min_initial_rho), max_initial_rho +  0.1*(max_initial_rho-min_initial_rho) )
+    axDensity.legend()
+    lineMomentum, = axMomentum.plot([xmin+0.5*dx + i*dx for i in range(nx)], q_field, label='Momentum')
+    axMomentum.set(xlabel='x (m)', ylabel='Momentum')
+    axMomentum.set_xlim(xmin,xmax)
+    axMomentum.set_ylim(min_initial_q - 0.1*(max_initial_q-min_initial_q), max_initial_q +  0.1*(max_initial_q-min_initial_q) )
+    axMomentum.legend()
+    lineVelocity, = axVelocity.plot([xmin+0.5*dx + i*dx for i in range(nx)], v_field, label='Velocity')
+    axVelocity.set(xlabel='x (m)', ylabel='Velocity')
+    axVelocity.set_xlim(xmin,xmax)
+    axVelocity.set_ylim(min_initial_v - 0.4*abs(min_initial_v), max_initial_v +  0.05*abs(max_initial_v) )
+    axVelocity.legend()
+    linePressure, = axPressure.plot([xmin+0.5*dx + i*dx for i in range(nx)], p_field, label='Pressure')
+    axPressure.set(xlabel='x (m)', ylabel='Pressure')
+    axPressure.set_xlim(xmin,xmax)
+    axPressure.set_ylim(min_initial_p - 0.05*abs(min_initial_p), max_initial_p +  0.05*abs(max_initial_p) )
+    axPressure.ticklabel_format(axis='y', style='sci', scilimits=(0,0))
+    axPressure.legend()
+    # Video settings
+    FFMpegWriter = manimation.writers['ffmpeg']
+    metadata = dict(title="Upwind (Roe) scheme with entropic correction for the 1D isothermal Euler System", artist = "CEA Saclay", comment="Shock tube")
+    writer=FFMpegWriter(fps=10, metadata=metadata, codec='h264')
+    with writer.saving(fig, "1DEuler_System_Upwind"+".mp4", ntmax):
+        writer.grab_frame()
+        plt.savefig("EulerSystem"+str(dim)+"UpwindExplicit"+meshName+"_0"+".png")
+
+        # loop in time
+        while (it<ntmax and time <= tmax ):
+            # time step
+            dt=compTimeStep(UU,dx,CFL);
+            # Neumann boundary condition
+            UU_limL[0] = UU[0,0];
+            UU_limL[1] = UU[0,1];
+            UU_limR[0] = UU[M.getNumberOfCells()-1,0];
+            UU_limR[1] = UU[M.getNumberOfCells()-1,1];
+            flux_iminus = flux(UU_limL[0],UU_limL[1]);
+            #Main loop on cells
+            for i in range(0,M.getNumberOfCells()):
+                if (i<M.getNumberOfCells()-1):
+                    Del_UU_RL[0]=UU[i+1,0]-UU[i,0];
+                    Del_UU_RL[1]=UU[i+1,1]-UU[i,1];
+                    AbsRoeMa = AbsRoeMatrix(UU[i,0],UU[i,1],UU[i+1,0],UU[i+1,1]);
+                    flux_iplus = (flux(UU[i,0],UU[i,1])+flux(UU[i+1,0],UU[i+1,1]))-AbsRoeMa*Del_UU_RL - Del_UU_RL*abs(UU[i+1,1]/UU[i+1,0]-UU[i,1]/UU[i,0])#The last term is the entropic correction
+                    flux_iplus[0]*=0.5;
+                    flux_iplus[1]*=0.5;
+                else:
+                    flux_iplus= flux(UU_limR[0],UU_limR[1]);
+                UU_new[i,0] = UU[i,0] - dt/dx*(flux_iplus[0]-flux_iminus[0]);
+                UU_new[i,1] = UU[i,1] - dt/dx*(flux_iplus[1]-flux_iminus[1]);
+                flux_iminus = flux_iplus;
+                pass
+            UU = UU_new;
+            time+=dt;
+            it+=1;
+
+            rho_field = [ UU[i,0]  for i in range(nx)]
+            q_field   = [ UU[i,1]  for i in range(nx)]
+            v_field   = [ UU[i,1]/UU[i,0]  for i in range(nx)]
+            p_field   = [ UU[i,0]*(c0*c0)  for i in range(nx)]
+
+            lineDensity.set_ydata(rho_field)
+            lineMomentum.set_ydata(q_field)
+            lineVelocity.set_ydata(v_field)
+            linePressure.set_ydata(p_field)
+            writer.grab_frame()
+
+            if (it%freqSortie==0):
+                print( "-- Iter : ", it," Time : ",time," dt : ",dt)
+                plt.savefig("EulerSystem"+str(dim)+"UpwindExplicit"+meshName+"_"+str(it)+".png")
+            pass
+
+    print("-- Iter: " + str(it) + ", Time: " + str(time) + ", dt: " + str(dt))
+    if(it>=ntmax):
+        print("Nombre de pas de temps maximum ntmax= ", ntmax, " atteint")
+        return
+    elif(isStationary):
+        print("Régime stationnaire atteint au pas de temps ", it, ", t= ", time)
+        print("------------------------------------------------------------------------------------")
+        plt.savefig("EulerSystem"+str(dim)+"UpwindExplicit"+meshName+"_Stat.png")
+        return
+    else:
+        print("Temps maximum Tmax= ", tmax, " atteint")
+
+    return
+
+if __name__ == '__main__':
+    main("SquareRegularSquares")
diff --git a/CDMATH/tests/examples/EulerSystem_Shock/EulerSystemStaggered/CMakeLists.txt b/CDMATH/tests/examples/EulerSystem_Shock/EulerSystemStaggered/CMakeLists.txt
new file mode 100755 (executable)
index 0000000..211c08d
--- /dev/null
@@ -0,0 +1,8 @@
+
+if (CDMATH_WITH_PYTHON AND CDMATH_WITH_PETSC AND CDMATH_WITH_POSTPRO)
+
+    ADD_TEST(ExampleEulerSystem_2DShock_ConservativeStaggered ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/EulerIsothermal_2DConservativeStaggered.py )
+
+endif (CDMATH_WITH_PYTHON AND CDMATH_WITH_PETSC AND CDMATH_WITH_POSTPRO)
+
+
diff --git a/CDMATH/tests/examples/EulerSystem_Shock/EulerSystemStaggered/EulerIsothermal_2DConservativeStaggered.py b/CDMATH/tests/examples/EulerSystem_Shock/EulerSystemStaggered/EulerIsothermal_2DConservativeStaggered.py
new file mode 100644 (file)
index 0000000..5480b7e
--- /dev/null
@@ -0,0 +1,798 @@
+#!/usr/bin/env python3\r
+# -*-coding:utf-8 -*\r
+\r
+#===============================================================================================================================\r
+# Name        : Résolution VF des équations d'Euler isotherme 2D sans terme source\r
+#                \partial_t rho + \div q = 0\r
+#                \partial_t q   + \div q \otimes q/rho   \grad p = 0\r
+# Author      : Michaël Ndjinga, Coraline Mounier\r
+# Copyright   : CEA Saclay 2020\r
+# Description : Propagation d'une onde de choc droite\r
+#               Utilisation du schéma upwind explicite ou implicite sur un maillage général\r
+#               Initialisation par une discontinuité verticale\r
+#               Conditions aux limites de Neumann\r
+#                Création et sauvegarde du champ résultant et des figures\r
+#================================================================================================================================\r
+\r
+\r
+import cdmath\r
+import numpy as np\r
+import matplotlib\r
+matplotlib.use("Agg")\r
+import matplotlib.pyplot as plt\r
+import matplotlib.animation as manimation\r
+from math import sqrt\r
+import sys\r
+import PV_routines\r
+\r
+p0=155.e5 #reference pressure in a pressurised nuclear vessel\r
+c0=700.   #reference sound speed for water at 155 bars\r
+rho0=p0/(c0*c0)   #reference density\r
+precision=1e-5\r
+\r
+def initial_conditions_Riemann_problem(my_mesh):\r
+    print( "Initial data : Riemann problem" )\r
+    dim     = my_mesh.getMeshDimension()\r
+    nbCells = my_mesh.getNumberOfCells()\r
+\r
+    xcentre = 0.5\r
+\r
+    density_field = cdmath.Field("Density",    cdmath.CELLS, my_mesh, 1)\r
+    q_x_field     = cdmath.Field("Momentum x", cdmath.CELLS, my_mesh, 1)\r
+    q_y_field     = cdmath.Field("Momentum y", cdmath.CELLS, my_mesh, 1)\r
+    #Velocity field with 3 components should be created for streamlines to be drawn\r
+    velocity_field = cdmath.Field("Velocity", cdmath.CELLS, my_mesh, 3)\r
+\r
+    for i in range(nbCells):\r
+        x = my_mesh.getCell(i).x()\r
+\r
+        # Initial momentum is zero\r
+        q_x_field[i] = 0\r
+        q_y_field[i] = 0\r
+\r
+        # Initial velocity is zero\r
+        velocity_field[i,0] = 0\r
+        velocity_field[i,1] = 0\r
+        velocity_field[i,2] = 0\r
+\r
+        if x < xcentre:\r
+            density_field[i] = rho0\r
+            pass\r
+        else:\r
+            density_field[i] = rho0/2\r
+            pass\r
+        pass\r
+\r
+    return density_field, q_x_field, q_y_field, velocity_field\r
+\r
+\r
+def jacobianMatricesm_x(coeff,rho_l,q_lx,q_ly,rho_r,q_rx,q_ry):\r
+    RoeMatx = cdmath.Matrix(3,3);\r
+    Dmacx = cdmath.Matrix(3,3);\r
+\r
+    u_lx=q_lx/rho_l\r
+    u_rx=q_rx/rho_r\r
+    u_ly=q_ly/rho_l\r
+    u_ry=q_ry/rho_r\r
+    if rho_l<0 or rho_r<0:\r
+        print("rho_l=",rho_l, " rho_r= ",rho_r)\r
+        raise ValueError("Negative density")\r
+    ux = (u_lx*sqrt(rho_l)+u_rx*sqrt(rho_r))/(sqrt(rho_l)+sqrt(rho_r));\r
+    uy = (u_ly*sqrt(rho_l)+u_ry*sqrt(rho_r))/(sqrt(rho_l)+sqrt(rho_r));\r
+\r
+    RoeMatx[0,0] = 0\r
+    RoeMatx[0,1] = 1\r
+    RoeMatx[0,2] = 0\r
+    RoeMatx[1,0] = c0*c0 - ux*ux\r
+    RoeMatx[1,1] = 2*ux\r
+    RoeMatx[1,2] = 0\r
+    RoeMatx[2,0] = -ux*uy\r
+    RoeMatx[2,1] = uy\r
+    RoeMatx[2,2] = ux\r
+\r
+    Dmacx[0,0] = abs(ux)-ux\r
+    Dmacx[0,1] = 1\r
+    Dmacx[0,2] = 0\r
+    Dmacx[1,0] = -c0*c0-ux*ux\r
+    Dmacx[1,1] = abs(ux)+ux\r
+    Dmacx[1,2] = 0\r
+    Dmacx[2,0] = -ux*uy\r
+    Dmacx[2,1] = uy\r
+    Dmacx[2,2] = abs(ux)\r
+\r
+    return (RoeMatx-Dmacx)*coeff*0.5\r
+\r
+def jacobianMatricesp_x(coeff,rho_l,q_lx,q_ly,rho_r,q_rx,q_ry):\r
+    RoeMatx   = cdmath.Matrix(3,3)\r
+    Dmacx = cdmath.Matrix(3,3)\r
+\r
+    u_lx=q_lx/rho_l\r
+    u_rx=q_rx/rho_r\r
+    u_ly=q_ly/rho_l\r
+    u_ry=q_ry/rho_r\r
+    if rho_l<0 or rho_r<0:\r
+        print("rho_l=",rho_l, " rho_r= ",rho_r)\r
+        raise ValueError("Negative density")\r
+    ux = (u_lx*sqrt(rho_l)+u_rx*sqrt(rho_r))/(sqrt(rho_l)+sqrt(rho_r));\r
+    uy = (u_ly*sqrt(rho_l)+u_ry*sqrt(rho_r))/(sqrt(rho_l)+sqrt(rho_r));\r
+\r
+    RoeMatx[0,0] = 0\r
+    RoeMatx[0,1] = 1\r
+    RoeMatx[0,2] = 0\r
+    RoeMatx[1,0] = c0*c0 - ux*ux\r
+    RoeMatx[1,1] = 2*ux\r
+    RoeMatx[1,2] = 0\r
+    RoeMatx[2,0] = -ux*uy\r
+    RoeMatx[2,1] = uy\r
+    RoeMatx[2,2] = ux\r
+\r
+    Dmacx[0,0] = abs(ux)-ux\r
+    Dmacx[0,1] = 1\r
+    Dmacx[0,2] = 0\r
+    Dmacx[1,0] = -c0*c0-ux*ux\r
+    Dmacx[1,1] = abs(ux)+ux\r
+    Dmacx[1,2] = 0\r
+    Dmacx[2,0] = -ux*uy\r
+    Dmacx[2,1] = uy\r
+    Dmacx[2,2] = abs(ux)\r
+\r
+    return (RoeMatx+Dmacx)*coeff*0.5\r
+\r
+def jacobianMatricesm_y(coeff,rho_l,q_lx,q_ly,rho_r,q_rx,q_ry):\r
+    RoeMaty   = cdmath.Matrix(3,3);\r
+    Dmacy = cdmath.Matrix(3,3);\r
+\r
+    u_lx=q_lx/rho_l\r
+    u_rx=q_rx/rho_r\r
+    u_ly=q_ly/rho_l\r
+    u_ry=q_ry/rho_r\r
+    if rho_l<0 or rho_r<0:\r
+        print("rho_l=",rho_l, " rho_r= ",rho_r)\r
+        raise ValueError("Negative density")\r
+    ux = (u_lx*sqrt(rho_l)+u_rx*sqrt(rho_r))/(sqrt(rho_l)+sqrt(rho_r));\r
+    uy = (u_ly*sqrt(rho_l)+u_ry*sqrt(rho_r))/(sqrt(rho_l)+sqrt(rho_r));\r
+\r
+    RoeMaty[0,0] = 0\r
+    RoeMaty[0,1] = 0\r
+    RoeMaty[0,2] = 1\r
+    RoeMaty[1,0] = -ux*uy\r
+    RoeMaty[1,1] = uy\r
+    RoeMaty[1,2] = ux\r
+    RoeMaty[2,0] = c0*c0-uy*uy\r
+    RoeMaty[2,1] = 0\r
+    RoeMaty[2,2] = 2*uy\r
+\r
+    Dmacy[0,0] = abs(uy)-uy\r
+    Dmacy[0,1] = 0\r
+    Dmacy[0,2] = 1\r
+    Dmacy[1,0] = -ux*uy\r
+    Dmacy[1,1] = abs(uy)\r
+    Dmacy[1,2] = ux\r
+    Dmacy[2,0] = -c0*c0-uy*uy\r
+    Dmacy[2,1] = 0\r
+    Dmacy[2,2] = abs(uy)+uy\r
+\r
+    return (RoeMaty-Dmacy)*coeff*0.5\r
+\r
+def jacobianMatricesp_y(coeff,rho_l,q_lx,q_ly,rho_r,q_rx,q_ry):\r
+    RoeMaty   = cdmath.Matrix(3,3);\r
+    Dmacy = cdmath.Matrix(3,3);\r
+\r
+    u_lx=q_lx/rho_l\r
+    u_rx=q_rx/rho_r\r
+    u_ly=q_ly/rho_l\r
+    u_ry=q_ry/rho_r\r
+    if rho_l<0 or rho_r<0:\r
+        print("rho_l=",rho_l, " rho_r= ",rho_r)\r
+        raise ValueError("Negative density")\r
+    ux = (u_lx*sqrt(rho_l)+u_rx*sqrt(rho_r))/(sqrt(rho_l)+sqrt(rho_r));\r
+    uy = (u_ly*sqrt(rho_l)+u_ry*sqrt(rho_r))/(sqrt(rho_l)+sqrt(rho_r));\r
+\r
+    RoeMaty[0,0] = 0\r
+    RoeMaty[0,1] = 0\r
+    RoeMaty[0,2] = 1\r
+    RoeMaty[1,0] = -ux*uy\r
+    RoeMaty[1,1] = uy\r
+    RoeMaty[1,2] = ux\r
+    RoeMaty[2,0] = c0*c0-uy*uy\r
+    RoeMaty[2,1] = 0\r
+    RoeMaty[2,2] = 2*uy\r
+\r
+    Dmacy[0,0] = abs(uy)-uy\r
+    Dmacy[0,1] = 0\r
+    Dmacy[0,2] = 1\r
+    Dmacy[1,0] = -ux*uy\r
+    Dmacy[1,1] = abs(uy)\r
+    Dmacy[1,2] = ux\r
+    Dmacy[2,0] = -c0*c0-uy*uy\r
+    Dmacy[2,1] = 0\r
+    Dmacy[2,2] = abs(uy)+uy\r
+\r
+    return (RoeMaty+Dmacy)*coeff*0.5\r
+\r
+def EulerSystemStaggered(ntmax, tmax, cfl,output_freq, my_mesh, meshName):\r
+\r
+    if not my_mesh.isStructured() :\r
+        raise ValueError("Euler_ConservativeStaggered2D_RiemannProblem.py expects a structured mesh")\r
+\r
+    dim=my_mesh.getMeshDimension()\r
+    if dim != 2 :\r
+        raise ValueError("Euler_ConservativeStaggered2D_RiemannProblem.py expects a 2D mesh")\r
+\r
+    nbComp=dim+1\r
+    # Mesh parameters\r
+    nbCells = my_mesh.getNumberOfCells()\r
+    nbCells_x = my_mesh.getNx()\r
+    nbCells_y = my_mesh.getNy()\r
+    dx,dy = my_mesh.getDXYZ()\r
+    nbVoisinsMax=my_mesh.getMaxNbNeighbours(cdmath.CELLS)\r
+    dx_min=my_mesh.minRatioVolSurf()\r
+    \r
+    # Time evolution parameters\r
+    time = 0.\r
+    it=0;\r
+    isStationary=False\r
+    iterGMRESMax = 50\r
+    newton_max   = 50\r
+\r
+    #iteration vectors\r
+    Un =cdmath.Vector(nbCells*nbComp)\r
+    dUn=cdmath.Vector(nbCells*nbComp)\r
+    dUk=cdmath.Vector(nbCells*nbComp)\r
+    Rhs=cdmath.Vector(nbCells*nbComp)\r
+\r
+    dUi_x=cdmath.Vector(nbComp)\r
+    dUi_y=cdmath.Vector(nbComp)\r
+    dUi1_x=cdmath.Vector(nbComp)\r
+    dUi2_x=cdmath.Vector(nbComp)\r
+    dUi1_y=cdmath.Vector(nbComp)\r
+    dUi2_y=cdmath.Vector(nbComp)\r
+\r
+    # Initial conditions #\r
+    print("Construction of the initial condition …")\r
+    rho_field, q_x_field, q_y_field, velocity_field= initial_conditions_Riemann_problem(my_mesh)\r
+\r
+    for i in range(nbCells):\r
+        Un[nbComp*i]   = rho_field[i]\r
+        Un[nbComp*i+1] = q_x_field[i]\r
+        Un[nbComp*i+2] = q_y_field[i]\r
+\r
+    #Sauvegarde de la donnée initiale\r
+    rho_field.setTime(time,it);\r
+    rho_field.writeVTK("EulerIsothermal_"+str(dim)+"DConservativeStaggered_"+meshName+"_density");\r
+    q_x_field.setTime(time,it);\r
+    q_x_field.writeVTK("EulerIsothermal_"+str(dim)+"DConservativeStaggered_"+meshName+"_momentumX");\r
+    q_y_field.setTime(time,it);\r
+    q_y_field.writeVTK("EulerIsothermal_"+str(dim)+"DConservativeStaggered_"+meshName+"_momentumY");\r
+    velocity_field.setTime(time,it);\r
+    velocity_field.writeVTK("EulerIsothermal_"+str(dim)+"DConservativeStaggered_"+meshName+"_velocity");\r
+\r
+    print("Starting computation of the isothermal Euler system with a conservative staggered scheme …")\r
+    divMat=cdmath.SparseMatrixPetsc(nbCells*nbComp,nbCells*nbComp,(nbVoisinsMax+1)*nbComp)\r
+\r
+    # Starting time loop\r
+    while (it<ntmax and time <= tmax and not isStationary):\r
+        dUn = Un.deepCopy()\r
+        Uk  = Un.deepCopy()\r
+        residu = 1e10\r
+        k=0\r
+        while (k<newton_max and residu > 1/precision ):\r
+\r
+            dt = cfl * dx_min / c0# This choice should be improved when possible by using the actual eigenvalue abs(u)+c0, that is the time step should be determined avec the computation of the jacobian matrices\r
+            #DEBUT BOUCLE NEWTON\r
+            for j in range(nbCells_y):\r
+                for i in range(nbCells_x):\r
+                    #Traitement des coins\r
+                    if ( j==0 and i==0) :\r
+                        #Calcul de Am_x\r
+                        rho_l=Uk[3*nbCells_x*j+3*i]\r
+                        qx_l =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_l =Uk[3*nbCells_x*j+3*i+2]\r
+                        rho_r=Uk[3*nbCells_x*j+3*(i+1)]\r
+                        qx_r =Uk[3*nbCells_x*j+3*(i+1)+1]\r
+                        qy_r =Uk[3*nbCells_x*j+3*(i+1)+2]\r
+                        Am_x= jacobianMatricesm_x(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        #calcul de Am_y\r
+                        rho_l=Uk[3*nbCells_x*j+3*i]\r
+                        qx_l =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_l =Uk[3*nbCells_x*j+3*i+2]\r
+                        rho_r=Uk[3*nbCells_x*(j+1)+3*i]\r
+                        qx_r =Uk[3*nbCells_x*(j+1)+3*i+1]\r
+                        qy_r =Uk[3*nbCells_x*(j+1)+3*i+2]\r
+                        Am_y= jacobianMatricesm_y(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*(i+1),Am_x)\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*(j+1)+3*i,Am_y)\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*i,Am_x*(-1.)-Am_y)\r
+\r
+                        dUi_x[0] = Uk[3*nbCells_x*j+3*(i+1)]-Uk[3*nbCells_x*j+3*i]\r
+                        dUi_x[1] = Uk[3*nbCells_x*j+3*(i+1)+1]-Uk[3*nbCells_x*j+3*i+1]\r
+                        dUi_x[2] = Uk[3*nbCells_x*j+3*(i+1)+2]-Uk[3*nbCells_x*j+3*i+2]\r
+                        dUi_y[0] = Uk[3*nbCells_x*(j+1)+3*i]-Uk[3*nbCells_x*j+3*i]\r
+                        dUi_y[1] = Uk[3*nbCells_x*(j+1)+3*i+1]-Uk[3*nbCells_x*j+3*i+1]\r
+                        dUi_y[2] = Uk[3*nbCells_x*(j+1)+3*i+2]-Uk[3*nbCells_x*j+3*i+2]\r
+\r
+                        temp_x = Am_x*dUi_x\r
+                        temp_y = Am_y*dUi_y\r
+                        #print("Bloc 0 matrix  :   ", Am)\r
+                        Rhs[3*nbCells_x*j+3*i+0] = -temp_x[0] - temp_y[0]-(Uk[3*nbCells_x*j+3*i+0]-Un[3*nbCells_x*j+3*i+0])\r
+                        Rhs[3*nbCells_x*j+3*i+1] = -temp_x[1] - temp_y[1]-(Uk[3*nbCells_x*j+3*i+1]-Un[3*nbCells_x*j+3*i+1])\r
+                        Rhs[3*nbCells_x*j+3*i+2] = -temp_x[2] - temp_y[2]-(Uk[3*nbCells_x*j+3*i+2]-Un[3*nbCells_x*j+3*i+2])\r
+\r
+                    elif(i==0 and j==nbCells_y-1):\r
+                        #Calcul de Am_x\r
+                        rho_l=Uk[3*nbCells_x*j+3*i]\r
+                        qx_l =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_l =Uk[3*nbCells_x*j+3*i+2]\r
+                        rho_r=Uk[3*nbCells_x*j+3*(i+1)]\r
+                        qx_r =Uk[3*nbCells_x*j+3*(i+1)+1]\r
+                        qy_r =Uk[3*nbCells_x*j+3*(i+1)+2]\r
+                        Am_x= jacobianMatricesm_x(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        #calcul de Ap_y\r
+                        rho_l=Uk[3*nbCells_x*(j-1)+3*i]\r
+                        qx_l =Uk[3*nbCells_x*(j-1)+3*i+1]\r
+                        qy_l =Uk[3*nbCells_x*(j-1)+3*i+2]\r
+                        rho_r=Uk[3*nbCells_x*j+3*i]\r
+                        qx_r =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_r =Uk[3*nbCells_x*j+3*i+2]\r
+                        Ap_y= jacobianMatricesp_y(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*(i+1),Am_x)\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*(j-1)+3*i,Ap_y*(-1.))\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*i,Am_x*(-1.)+Ap_y)\r
+\r
+                        dUi_x[0] = Uk[3*nbCells_x*j+3*(i+1)]-Uk[3*nbCells_x*j+3*i]\r
+                        dUi_x[1] = Uk[3*nbCells_x*j+3*(i+1)+1]-Uk[3*nbCells_x*j+3*i+1]\r
+                        dUi_x[2] = Uk[3*nbCells_x*j+3*(i+1)+2]-Uk[3*nbCells_x*j+3*i+2]\r
+                        dUi_y[0] = Uk[3*nbCells_x*j+3*i]-Uk[3*nbCells_x*(j-1)+3*i]\r
+                        dUi_y[1] = Uk[3*nbCells_x*j+3*i+1]-Uk[3*nbCells_x*(j-1)+3*i+1]\r
+                        dUi_y[2] = Uk[3*nbCells_x*j+3*i+2]-Uk[3*nbCells_x*(j-1)+3*i+2]\r
+\r
+                        temp_x = Am_x*dUi_x\r
+                        temp_y = Ap_y*dUi_y\r
+                        #print("Bloc 0 matrix  :   ", Am)\r
+                        Rhs[3*nbCells_x*j+3*i+0] = -temp_x[0]- temp_y[0]-(Uk[3*nbCells_x*j+3*i+0]-Un[3*nbCells_x*j+3*i+0])\r
+                        Rhs[3*nbCells_x*j+3*i+1] = -temp_x[1]- temp_y[1]-(Uk[3*nbCells_x*j+3*i+1]-Un[3*nbCells_x*j+3*i+1])\r
+                        Rhs[3*nbCells_x*j+3*i+2] = -temp_x[2]- temp_y[2]-(Uk[3*nbCells_x*j+3*i+2]-Un[3*nbCells_x*j+3*i+2])\r
+\r
+                    elif(i==nbCells_x-1 and j==0):\r
+\r
+                        #Calcul de Ap_x\r
+                        rho_l=Uk[3*nbCells_x*j+3*(i-1)]\r
+                        qx_l =Uk[3*nbCells_x*j+3*(i-1)+1]\r
+                        qy_l =Uk[3*nbCells_x*j+3*(i-1)+2]\r
+                        rho_r=Uk[3*nbCells_x*j+3*i]\r
+                        qx_r =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_r =Uk[3*nbCells_x*j+3*i+2]\r
+                        Ap_x= jacobianMatricesp_x(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        #calcul de Am_y\r
+                        rho_l=Uk[3*nbCells_x*j+3*i]\r
+                        qx_l =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_l =Uk[3*nbCells_x*j+3*i+2]\r
+                        rho_r=Uk[3*nbCells_x*(j+1)+3*i]\r
+                        qx_r =Uk[3*nbCells_x*(j+1)+3*i+1]\r
+                        qy_r =Uk[3*nbCells_x*(j+1)+3*i+2]\r
+                        Am_y= jacobianMatricesm_y(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*(i-1),Ap_x*(-1))\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*(j+1)+3*i,Am_y)\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*i,Ap_x-Am_y)\r
+\r
+                        dUi_x[0] = Uk[3*nbCells_x*j+3*i]-Uk[3*nbCells_x*j+3*(i-1)]\r
+                        dUi_x[1] = Uk[3*nbCells_x*j+3*i+1]-Uk[3*nbCells_x*j+3*(i-1)+1]\r
+                        dUi_x[2] = Uk[3*nbCells_x*j+3*i+2]-Uk[3*nbCells_x*j+3*(i-1)+2]\r
+                        dUi_y[0] = Uk[3*nbCells_x*(j+1)+3*i]-Uk[3*nbCells_x*j+3*i]\r
+                        dUi_y[1] = Uk[3*nbCells_x*(j+1)+3*i+1]-Uk[3*nbCells_x*j+3*i+1]\r
+                        dUi_y[2] = Uk[3*nbCells_x*(j+1)+3*i+2]-Uk[3*nbCells_x*j+3*i+2]\r
+\r
+                        temp_x = Ap_x*dUi_x\r
+                        temp_y= Am_y*dUi_y\r
+                        #print("Bloc 0 matrix  :   ", Am)\r
+                        Rhs[3*nbCells_x*j+3*i+0] = -temp_x[0]- temp_y[0]-(Uk[3*nbCells_x*j+3*i+0]-Un[3*nbCells_x*j+3*i+0])\r
+                        Rhs[3*nbCells_x*j+3*i+1] = -temp_x[1]- temp_y[1]-(Uk[3*nbCells_x*j+3*i+1]-Un[3*nbCells_x*j+3*i+1])\r
+                        Rhs[3*nbCells_x*j+3*i+2] = -temp_x[2]- temp_y[2]-(Uk[3*nbCells_x*j+3*i+2]-Un[3*nbCells_x*j+3*i+2])\r
+\r
+                    elif ( j==nbCells_y-1 and i==nbCells_x-1) :\r
+\r
+                        #Calcul de Ap_x\r
+                        rho_l=Uk[3*nbCells_x*j+3*(i-1)]\r
+                        qx_l =Uk[3*nbCells_x*j+3*(i-1)+1]\r
+                        qy_l =Uk[3*nbCells_x*j+3*(i-1)+2]\r
+                        rho_r=Uk[3*nbCells_x*j+3*i]\r
+                        qx_r =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_r =Uk[3*nbCells_x*j+3*i+2]\r
+                        Ap_x= jacobianMatricesp_x(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        #calcul de Ap_y\r
+                        rho_l=Uk[3*nbCells_x*(j-1)+3*i]\r
+                        qx_l =Uk[3*nbCells_x*(j-1)+3*i+1]\r
+                        qy_l =Uk[3*nbCells_x*(j-1)+3*i+2]\r
+                        rho_r=Uk[3*nbCells_x*j+3*i]\r
+                        qx_r =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_r =Uk[3*nbCells_x*j+3*i+2]\r
+                        Ap_y= jacobianMatricesp_y(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*(i-1),Ap_x*(-1.))\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*(j-1)+3*i,Ap_y*(-1.))\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*i,Ap_x+Ap_y)\r
+\r
+                        dUi_x[0] = Uk[3*nbCells_x*j+3*i]-Uk[3*nbCells_x*j+3*(i-1)]\r
+                        dUi_x[1] = Uk[3*nbCells_x*j+3*i+1]-Uk[3*nbCells_x*j+3*(i-1)+1]\r
+                        dUi_x[2] = Uk[3*nbCells_x*j+3*i+2]-Uk[3*nbCells_x*j+3*(i-1)+2]\r
+                        dUi_y[0] = Uk[3*nbCells_x*j+3*i]-Uk[3*nbCells_x*(j-1)+3*i]\r
+                        dUi_y[1] = Uk[3*nbCells_x*j+3*i+1]-Uk[3*nbCells_x*(j-1)+3*i+1]\r
+                        dUi_y[2] = Uk[3*nbCells_x*j+3*i+2]-Uk[3*nbCells_x*(j-1)+3*i+2]\r
+\r
+                        temp_x = Ap_x*dUi_x\r
+                        temp_y = Ap_y*dUi_y\r
+                        Rhs[3*nbCells_x*j+3*i+0] = -temp_x[0]-temp_y[0]-(Uk[3*nbCells_x*j+3*i+0]-Un[3*nbCells_x*j+3*i+0])\r
+                        Rhs[3*nbCells_x*j+3*i+1] = -temp_x[1]-temp_y[1]-(Uk[3*nbCells_x*j+3*i+1]-Un[3*nbCells_x*j+3*i+1])\r
+                        Rhs[3*nbCells_x*j+3*i+2] = -temp_x[2]-temp_y[2]-(Uk[3*nbCells_x*j+3*i+2]-Un[3*nbCells_x*j+3*i+2])\r
+\r
+                    #Traitement des bords restants\r
+                    elif i==0 :\r
+\r
+                        #Calcul de Am_x\r
+                        rho_l=Uk[3*nbCells_x*j+3*i]\r
+                        qx_l =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_l =Uk[3*nbCells_x*j+3*i+2]\r
+                        rho_r=Uk[3*nbCells_x*j+3*(i+1)]\r
+                        qx_r =Uk[3*nbCells_x*j+3*(i+1)+1]\r
+                        qy_r =Uk[3*nbCells_x*j+3*(i+1)+2]\r
+                        Am_x= jacobianMatricesm_x(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        #calcul de Am_y\r
+                        rho_l=Uk[3*nbCells_x*j+3*i]\r
+                        qx_l =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_l =Uk[3*nbCells_x*j+3*i+2]\r
+                        rho_r=Uk[3*nbCells_x*(j+1)+3*i]\r
+                        qx_r =Uk[3*nbCells_x*(j+1)+3*i+1]\r
+                        qy_r =Uk[3*nbCells_x*(j+1)+3*i+2]\r
+                        Am_y= jacobianMatricesm_y(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        #calcul de Ap_y\r
+                        rho_l=Uk[3*nbCells_x*(j-1)+3*i]\r
+                        qx_l =Uk[3*nbCells_x*(j-1)+3*i+1]\r
+                        qy_l =Uk[3*nbCells_x*(j-1)+3*i+2]\r
+                        rho_r=Uk[3*nbCells_x*j+3*i]\r
+                        qx_r =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_r =Uk[3*nbCells_x*j+3*i+2]\r
+                        Ap_y= jacobianMatricesp_y(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        #remplissage de la divMat\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*(i+1),Am_x)\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*(j+1)+3*i,Am_y)\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*(j-1)+3*i,Ap_y*(-1.))\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*i,Ap_y-Am_x-Am_y)\r
+\r
+                        #remplissage du membre de droite\r
+                        dUi_x[0] = Uk[3*nbCells_x*j+3*(i+1)]-Uk[3*nbCells_x*j+3*i]\r
+                        dUi_x[1] = Uk[3*nbCells_x*j+3*(i+1)+1]-Uk[3*nbCells_x*j+3*i+1]\r
+                        dUi_x[2] = Uk[3*nbCells_x*j+3*(i+1)+2]-Uk[3*nbCells_x*j+3*i+2]\r
+                        dUi1_y[0] = Uk[3*nbCells_x*(j+1)+3*i]-Uk[3*nbCells_x*j+3*i]\r
+                        dUi1_y[1] = Uk[3*nbCells_x*(j+1)+3*i+1]-Uk[3*nbCells_x*j+3*i+1]\r
+                        dUi1_y[2] = Uk[3*nbCells_x*(j+1)+3*i+2]-Uk[3*nbCells_x*j+3*i+2]\r
+                        dUi2_y[0] = Uk[3*nbCells_x*j+3*i]-Uk[3*nbCells_x*(j-1)+3*i]\r
+                        dUi2_y[1] = Uk[3*nbCells_x*j+3*i+1]-Uk[3*nbCells_x*(j-1)+3*i+1]\r
+                        dUi2_y[2] = Uk[3*nbCells_x*j+3*i+2]-Uk[3*nbCells_x*(j-1)+3*i+2]\r
+\r
+                        temp_x  = Am_x*dUi_x\r
+                        temp1_y = Am_y*dUi1_y\r
+                        temp2_y = Ap_y*dUi2_y\r
+                        Rhs[3*nbCells_x*j+3*i+0] = -temp_x[0]-temp1_y[0]-temp2_y[0]-(Uk[3*nbCells_x*j+3*i+0]-Un[3*nbCells_x*j+3*i+0])\r
+                        Rhs[3*nbCells_x*j+3*i+1] = -temp_x[1]-temp1_y[1]-temp2_y[1]-(Uk[3*nbCells_x*j+3*i+1]-Un[3*nbCells_x*j+3*i+1])\r
+                        Rhs[3*nbCells_x*j+3*i+2] = -temp_x[2]-temp1_y[2]-temp2_y[2]-(Uk[3*nbCells_x*j+3*i+2]-Un[3*nbCells_x*j+3*i+2])\r
+\r
+                    elif i==nbCells_x-1:\r
+\r
+                        #Calcul de Ap_x\r
+                        rho_l=Uk[3*nbCells_x*j+3*(i-1)]\r
+                        qx_l =Uk[3*nbCells_x*j+3*(i-1)+1]\r
+                        qy_l =Uk[3*nbCells_x*j+3*(i-1)+2]\r
+                        rho_r=Uk[3*nbCells_x*j+3*i]\r
+                        qx_r =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_r =Uk[3*nbCells_x*j+3*i+2]\r
+                        Ap_x= jacobianMatricesp_x(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        #calcul de Am_y\r
+                        rho_l=Uk[3*nbCells_x*j+3*i]\r
+                        qx_l =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_l =Uk[3*nbCells_x*j+3*i+2]\r
+                        rho_r=Uk[3*nbCells_x*(j+1)+3*i]\r
+                        qx_r =Uk[3*nbCells_x*(j+1)+3*i+1]\r
+                        qy_r =Uk[3*nbCells_x*(j+1)+3*i+2]\r
+                        Am_y= jacobianMatricesm_y(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        #calcul de Ap_y\r
+                        rho_l=Uk[3*nbCells_x*(j-1)+3*i]\r
+                        qx_l =Uk[3*nbCells_x*(j-1)+3*i+1]\r
+                        qy_l =Uk[3*nbCells_x*(j-1)+3*i+2]\r
+                        rho_r=Uk[3*nbCells_x*j+3*i]\r
+                        qx_r =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_r =Uk[3*nbCells_x*j+3*i+2]\r
+                        Ap_y= jacobianMatricesp_y(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        #remplissage de la divMat\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*(i-1),Ap_x*(-1.))\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*(j+1)+3*i,Am_y)\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*(j-1)+3*i,Ap_y*(-1.))\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*i,Ap_y+Ap_x-Am_y)\r
+\r
+                        #remplissage du membre de droite\r
+                        dUi_x[0] = Uk[3*nbCells_x*j+3*i]-Uk[3*nbCells_x*j+3*(i-1)]\r
+                        dUi_x[1] = Uk[3*nbCells_x*j+3*i+1]-Uk[3*nbCells_x*j+3*(i-1)+1]\r
+                        dUi_x[2] = Uk[3*nbCells_x*j+3*i+2]-Uk[3*nbCells_x*j+3*(i-1)+2]\r
+                        dUi1_y[0] = Uk[3*nbCells_x*(j+1)+3*i]-Uk[3*nbCells_x*j+3*i]\r
+                        dUi1_y[1] = Uk[3*nbCells_x*(j+1)+3*i+1]-Uk[3*nbCells_x*j+3*i+1]\r
+                        dUi1_y[2] = Uk[3*nbCells_x*(j+1)+3*i+2]-Uk[3*nbCells_x*j+3*i+2]\r
+                        dUi2_y[0] = Uk[3*nbCells_x*j+3*i]-Uk[3*nbCells_x*(j-1)+3*i]\r
+                        dUi2_y[1] = Uk[3*nbCells_x*j+3*i+1]-Uk[3*nbCells_x*(j-1)+3*i+1]\r
+                        dUi2_y[2] = Uk[3*nbCells_x*j+3*i+2]-Uk[3*nbCells_x*(j-1)+3*i+2]\r
+\r
+                        temp_x  = Ap_x*dUi_x\r
+                        temp1_y = Am_y*dUi1_y\r
+                        temp2_y = Ap_y*dUi2_y\r
+                        Rhs[3*nbCells_x*j+3*i+0] = -temp_x[0]-temp1_y[0]-temp2_y[0]-(Uk[3*nbCells_x*j+3*i+0]-Un[3*nbCells_x*j+3*i+0])\r
+                        Rhs[3*nbCells_x*j+3*i+1] = -temp_x[1]-temp1_y[1]-temp2_y[1]-(Uk[3*nbCells_x*j+3*i+1]-Un[3*nbCells_x*j+3*i+1])\r
+                        Rhs[3*nbCells_x*j+3*i+2] = -temp_x[2]-temp1_y[2]-temp2_y[2]-(Uk[3*nbCells_x*j+3*i+2]-Un[3*nbCells_x*j+3*i+2])\r
+\r
+                    elif j==0:\r
+\r
+                        #Calcul de Am_x\r
+                        rho_l=Uk[3*nbCells_x*j+3*i]\r
+                        qx_l =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_l =Uk[3*nbCells_x*j+3*i+2]\r
+                        rho_r=Uk[3*nbCells_x*j+3*(i+1)]\r
+                        qx_r =Uk[3*nbCells_x*j+3*(i+1)+1]\r
+                        qy_r =Uk[3*nbCells_x*j+3*(i+1)+2]\r
+                        Am_x= jacobianMatricesm_x(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        #Calcul de Ap_x\r
+                        rho_l=Uk[3*nbCells_x*j+3*(i-1)]\r
+                        qx_l =Uk[3*nbCells_x*j+3*(i-1)+1]\r
+                        qy_l =Uk[3*nbCells_x*j+3*(i-1)+2]\r
+                        rho_r=Uk[3*nbCells_x*j+3*i]\r
+                        qx_r =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_r =Uk[3*nbCells_x*j+3*i+2]\r
+                        Ap_x= jacobianMatricesp_x(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        #calcul de Am_y\r
+                        rho_l=Uk[3*nbCells_x*j+3*i]\r
+                        qx_l =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_l =Uk[3*nbCells_x*j+3*i+2]\r
+                        rho_r=Uk[3*nbCells_x*(j+1)+3*i]\r
+                        qx_r =Uk[3*nbCells_x*(j+1)+3*i+1]\r
+                        qy_r =Uk[3*nbCells_x*(j+1)+3*i+2]\r
+                        Am_y= jacobianMatricesm_y(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        #remplissage de la divMat\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*(i-1),Ap_x*(-1.))\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*(i+1),Am_x)\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*(j+1)+3*i,Am_y)\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*i,Ap_x-Am_x-Am_y)\r
+\r
+                        #remplissage du membre de droite\r
+                        dUi1_x[0] = Uk[3*nbCells_x*j+3*(i+1)]-Uk[3*nbCells_x*j+3*i]\r
+                        dUi1_x[1] = Uk[3*nbCells_x*j+3*(i+1)+1]-Uk[3*nbCells_x*j+3*i+1]\r
+                        dUi1_x[2] = Uk[3*nbCells_x*j+3*(i+1)+2]-Uk[3*nbCells_x*j+3*i+2]\r
+                        dUi2_x[0] = Uk[3*nbCells_x*j+3*i]-Uk[3*nbCells_x*j+3*(i-1)]\r
+                        dUi2_x[1] = Uk[3*nbCells_x*j+3*i+1]-Uk[3*nbCells_x*j+3*(i-1)+1]\r
+                        dUi2_x[2] = Uk[3*nbCells_x*j+3*i+2]-Uk[3*nbCells_x*j+3*(i-1)+2]\r
+                        dUi_y[0] = Uk[3*nbCells_x*(j+1)+3*i]-Uk[3*nbCells_x*j+3*i]\r
+                        dUi_y[1] = Uk[3*nbCells_x*(j+1)+3*i+1]-Uk[3*nbCells_x*j+3*i+1]\r
+                        dUi_y[2] = Uk[3*nbCells_x*(j+1)+3*i+2]-Uk[3*nbCells_x*j+3*i+2]\r
+\r
+                        temp1_x = Am_x*dUi1_x\r
+                        temp2_x = Ap_x*dUi2_x\r
+                        temp_y = Am_y*dUi_y\r
+                        Rhs[3*nbCells_x*j+3*i+0] = -temp1_x[0]-temp2_x[0]-temp_y[0]-(Uk[3*nbCells_x*j+3*i+0]-Un[3*nbCells_x*j+3*i+0])\r
+                        Rhs[3*nbCells_x*j+3*i+1] = -temp1_x[1]-temp2_x[1]-temp_y[1]-(Uk[3*nbCells_x*j+3*i+1]-Un[3*nbCells_x*j+3*i+1])\r
+                        Rhs[3*nbCells_x*j+3*i+2] = -temp1_x[2]-temp2_x[2]-temp_y[2]-(Uk[3*nbCells_x*j+3*i+2]-Un[3*nbCells_x*j+3*i+2])\r
+\r
+                    elif j==nbCells_y-1:\r
+\r
+                        #Calcul de Am_x\r
+                        rho_l=Uk[3*nbCells_x*j+3*i]\r
+                        qx_l =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_l =Uk[3*nbCells_x*j+3*i+2]\r
+                        rho_r=Uk[3*nbCells_x*j+3*(i+1)]\r
+                        qx_r =Uk[3*nbCells_x*j+3*(i+1)+1]\r
+                        qy_r =Uk[3*nbCells_x*j+3*(i+1)+2]\r
+                        Am_x= jacobianMatricesm_x(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        #Calcul de Ap_x\r
+                        rho_l=Uk[3*nbCells_x*j+3*(i-1)]\r
+                        qx_l =Uk[3*nbCells_x*j+3*(i-1)+1]\r
+                        qy_l =Uk[3*nbCells_x*j+3*(i-1)+2]\r
+                        rho_r=Uk[3*nbCells_x*j+3*i]\r
+                        qx_r =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_r =Uk[3*nbCells_x*j+3*i+2]\r
+                        Ap_x= jacobianMatricesp_x(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        #calcul de Ap_y\r
+                        rho_l=Uk[3*nbCells_x*(j-1)+3*i]\r
+                        qx_l =Uk[3*nbCells_x*(j-1)+3*i+1]\r
+                        qy_l =Uk[3*nbCells_x*(j-1)+3*i+2]\r
+                        rho_r=Uk[3*nbCells_x*j+3*i]\r
+                        qx_r =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_r =Uk[3*nbCells_x*j+3*i+2]\r
+                        Ap_y= jacobianMatricesp_y(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        #remplissage de la divMat\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*(i-1),Ap_x*(-1.))\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*(i+1),Am_x)\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*(j-1)+3*i,Ap_y*(-1.))\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*i,Ap_x+Ap_y-Am_x)\r
+\r
+                        #remplissage du membre de droite\r
+                        dUi1_x[0] = Uk[3*nbCells_x*j+3*(i+1)]-Uk[3*nbCells_x*j+3*i]\r
+                        dUi1_x[1] = Uk[3*nbCells_x*j+3*(i+1)+1]-Uk[3*nbCells_x*j+3*i+1]\r
+                        dUi1_x[2] = Uk[3*nbCells_x*j+3*(i+1)+2]-Uk[3*nbCells_x*j+3*i+2]\r
+                        dUi2_x[0] = Uk[3*nbCells_x*j+3*i]-Uk[3*nbCells_x*j+3*(i-1)]\r
+                        dUi2_x[1] = Uk[3*nbCells_x*j+3*i+1]-Uk[3*nbCells_x*j+3*(i-1)+1]\r
+                        dUi2_x[2] = Uk[3*nbCells_x*j+3*i+2]-Uk[3*nbCells_x*j+3*(i-1)+2]\r
+                        dUi_y[0] = Uk[3*nbCells_x*j+3*i]-Uk[3*nbCells_x*(j-1)+3*i]\r
+                        dUi_y[1] = Uk[3*nbCells_x*j+3*i+1]-Uk[3*nbCells_x*(j-1)+3*i+1]\r
+                        dUi_y[2] = Uk[3*nbCells_x*j+3*i+2]-Uk[3*nbCells_x*(j-1)+3*i+2]\r
+\r
+                        temp1_x = Am_x*dUi1_x\r
+                        temp2_x = Ap_x*dUi2_x\r
+                        temp_y = Ap_y*dUi_y\r
+                        Rhs[3*nbCells_x*j+3*i+0] = -temp1_x[0]-temp2_x[0]-temp_y[0]-(Uk[3*nbCells_x*j+3*i+0]-Un[3*nbCells_x*j+3*i+0])\r
+                        Rhs[3*nbCells_x*j+3*i+1] = -temp1_x[1]-temp2_x[1]-temp_y[1]-(Uk[3*nbCells_x*j+3*i+1]-Un[3*nbCells_x*j+3*i+1])\r
+                        Rhs[3*nbCells_x*j+3*i+2] = -temp1_x[2]-temp2_x[2]-temp_y[2]-(Uk[3*nbCells_x*j+3*i+2]-Un[3*nbCells_x*j+3*i+2])\r
+\r
+                    #Traitement des autres cellules\r
+                    else:\r
+\r
+                        #Calcul de Am_x\r
+                        rho_l=Uk[3*nbCells_x*j+3*i]\r
+                        qx_l =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_l =Uk[3*nbCells_x*j+3*i+2]\r
+                        rho_r=Uk[3*nbCells_x*j+3*(i+1)]\r
+                        qx_r =Uk[3*nbCells_x*j+3*(i+1)+1]\r
+                        qy_r =Uk[3*nbCells_x*j+3*(i+1)+2]\r
+                        Am_x= jacobianMatricesm_x(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        #Calcul de Ap_x\r
+                        rho_l=Uk[3*nbCells_x*j+3*(i-1)]\r
+                        qx_l =Uk[3*nbCells_x*j+3*(i-1)+1]\r
+                        qy_l =Uk[3*nbCells_x*j+3*(i-1)+2]\r
+                        rho_r=Uk[3*nbCells_x*j+3*i]\r
+                        qx_r =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_r =Uk[3*nbCells_x*j+3*i+2]\r
+                        Ap_x= jacobianMatricesp_x(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        #calcul de Am_y\r
+                        rho_l=Uk[3*nbCells_x*j+3*i]\r
+                        qx_l =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_l =Uk[3*nbCells_x*j+3*i+2]\r
+                        rho_r=Uk[3*nbCells_x*(j+1)+3*i]\r
+                        qx_r =Uk[3*nbCells_x*(j+1)+3*i+1]\r
+                        qy_r =Uk[3*nbCells_x*(j+1)+3*i+2]\r
+                        Am_y= jacobianMatricesm_y(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        #calcul de Ap_y\r
+                        rho_l=Uk[3*nbCells_x*(j-1)+3*i]\r
+                        qx_l =Uk[3*nbCells_x*(j-1)+3*i+1]\r
+                        qy_l =Uk[3*nbCells_x*(j-1)+3*i+2]\r
+                        rho_r=Uk[3*nbCells_x*j+3*i]\r
+                        qx_r =Uk[3*nbCells_x*j+3*i+1]\r
+                        qy_r =Uk[3*nbCells_x*j+3*i+2]\r
+                        Ap_y= jacobianMatricesp_y(dt/dx,rho_l,qx_l,qy_l,rho_r,qx_r,qy_r)\r
+\r
+                        #remplissage de la divMat\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*(i-1),Ap_x*(-1.))\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*(j-1)+3*i,Ap_y*(-1.))\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*(i+1),Am_x)\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*(j+1)+3*i,Am_y)\r
+                        divMat.addValue(3*nbCells_x*j+3*i,3*nbCells_x*j+3*i,Ap_x+Ap_y-Am_x-Am_y)\r
+\r
+                        #remplissage du membre de droite\r
+\r
+                        dUi1_x[0] = Uk[3*nbCells_x*j+3*(i+1)]-Uk[3*nbCells_x*j+3*i]\r
+                        dUi1_x[1] = Uk[3*nbCells_x*j+3*(i+1)+1]-Uk[3*nbCells_x*j+3*i+1]\r
+                        dUi1_x[2] = Uk[3*nbCells_x*j+3*(i+1)+2]-Uk[3*nbCells_x*j+3*i+2]\r
+\r
+                        dUi2_x[0] = Uk[3*nbCells_x*j+3*i]-Uk[3*nbCells_x*j+3*(i-1)]\r
+                        dUi2_x[1] = Uk[3*nbCells_x*j+3*i+1]-Uk[3*nbCells_x*j+3*(i-1)+1]\r
+                        dUi2_x[2] = Uk[3*nbCells_x*j+3*i+2]-Uk[3*nbCells_x*j+3*(i-1)+2]\r
+\r
+                        dUi1_y[0] = Uk[3*nbCells_x*(j+1)+3*i]-Uk[3*nbCells_x*j+3*i]\r
+                        dUi1_y[1] = Uk[3*nbCells_x*(j+1)+3*i+1]-Uk[3*nbCells_x*j+3*i+1]\r
+                        dUi1_y[2] = Uk[3*nbCells_x*(j+1)+3*i+2]-Uk[3*nbCells_x*j+3*i+2]\r
+\r
+                        dUi2_y[0] = Uk[3*nbCells_x*j+3*i]-Uk[3*nbCells_x*(j-1)+3*i]\r
+                        dUi2_y[1] = Uk[3*nbCells_x*j+3*i+1]-Uk[3*nbCells_x*(j-1)+3*i+1]\r
+                        dUi2_y[2] = Uk[3*nbCells_x*j+3*i+2]-Uk[3*nbCells_x*(j-1)+3*i+2]\r
+\r
+                        temp1_x = Am_x*dUi1_x\r
+                        temp2_x = Ap_x*dUi2_x\r
+                        temp1_y = Am_y*dUi1_y\r
+                        temp2_y = Ap_y*dUi2_y\r
+                        Rhs[3*nbCells_x*j+3*i+0] = -temp1_x[0]-temp2_x[0]-temp1_y[0]-temp2_y[0]-(Uk[3*nbCells_x*j+3*i+0]-Un[3*nbCells_x*j+3*i+0])\r
+                        Rhs[3*nbCells_x*j+3*i+1] = -temp1_x[1]-temp2_x[1]-temp1_y[1]-temp2_y[1]-(Uk[3*nbCells_x*j+3*i+1]-Un[3*nbCells_x*j+3*i+1])\r
+                        Rhs[3*nbCells_x*j+3*i+2] = -temp1_x[2]-temp2_x[2]-temp1_y[2]-temp2_y[2]-(Uk[3*nbCells_x*j+3*i+2]-Un[3*nbCells_x*j+3*i+2])\r
+\r
+            divMat.diagonalShift(1)  #only after  filling all coefficients\r
+            LS=cdmath.LinearSolver(divMat,Rhs,iterGMRESMax, precision, "GMRES","LU")\r
+            dUk=LS.solve();\r
+            residu = dUk.norm()\r
+            Uk+=dUk\r
+            #print("Newton iteration number ",k, "residu = ",residu)\r
+            if(not LS.getStatus()):\r
+                print("Linear system did not converge ", LS.getNumberOfIter(), " GMRES iterations")\r
+                raise ValueError("Pas de convergence du système linéaire");\r
+            k=k+1\r
+        Un = Uk.deepCopy()\r
+        dUn-=Un\r
+        isStationary = dUn.norm()<precision\r
+        \r
+        for i in range(nbCells):\r
+            rho_field[i] = Un[nbComp*i]\r
+            q_x_field[i] = Un[nbComp*i+1]\r
+            q_y_field[i] = Un[nbComp*i+2]\r
+\r
+        time=time+dt;\r
+        it=it+1;\r
+        #Sauvegardes\r
+        if(it==1 or it%output_freq==0 or it>=ntmax or isStationary or time >=tmax):\r
+            print("-- Iter: " + str(it) + ", Time: " + str(time) + ", dt: " + str(dt) + ", Newton iterations: "+str(k)+", ||dUn|| = "+str(dUn.norm()))\r
+            print("Linear system converged in ", LS.getNumberOfIter(), " GMRES iterations, résidu = ", residu)\r
+            for k in range(nbCells):\r
+                rho  =rho_field[k]\r
+                velocity_field[k,0]=q_x_field[i]/rho\r
+                if(dim>1):\r
+                    velocity_field[k,1]=q_y_field[k]/rho\r
+            print\r
+            rho_field.setTime(time,it);\r
+            rho_field.writeVTK("EulerIsothermal_"+str(dim)+"DConservativeStaggered_"+meshName+"_density",False);\r
+            q_x_field.setTime(time,it);\r
+            q_x_field.writeVTK("EulerIsothermal_"+str(dim)+"DConservativeStaggered_"+meshName+"_momentumX",False);\r
+            q_y_field.setTime(time,it);\r
+            q_y_field.writeVTK("EulerIsothermal_"+str(dim)+"DConservativeStaggered_"+meshName+"_momentumY",False);\r
+            velocity_field.setTime(time,it);\r
+            velocity_field.writeVTK("EulerIsothermal_"+str(dim)+"DConservativeStaggered_"+meshName+"_velocity",False);\r
+            #Postprocessing : save 2D picture\r
+            PV_routines.Save_PV_data_to_picture_file("EulerIsothermal_"+str(dim)+"DConservativeStaggered_"+meshName+"_density_"  +str(it)+'.vtu',"Density",   'CELLS',"EulerIsothermal_"+str(dim)+"DConservativeStaggered_"+meshName+"_density"  +str(it))\r
+            PV_routines.Save_PV_data_to_picture_file("EulerIsothermal_"+str(dim)+"DConservativeStaggered_"+meshName+"_momentumX_"+str(it)+'.vtu',"Momentum x",'CELLS',"EulerIsothermal_"+str(dim)+"DConservativeStaggered_"+meshName+"_momentumX"+str(it))\r
+            PV_routines.Save_PV_data_to_picture_file("EulerIsothermal_"+str(dim)+"DConservativeStaggered_"+meshName+"_momentumY_"+str(it)+'.vtu',"Momentum y",'CELLS',"EulerIsothermal_"+str(dim)+"DConservativeStaggered_"+meshName+"_momentumY"+str(it))\r
+    print("-- Iter: " + str(it) + ", Time: " + str(time) + ", dt: " + str(dt))\r
+    if(it>=ntmax):\r
+        print("Nombre de pas de temps maximum ntmax= ", ntmax, " atteint")\r
+        return\r
+    elif(isStationary):\r
+        print("Régime stationnaire atteint au pas de temps ", it, ", t= ", time)\r
+        print("------------------------------------------------------------------------------------")\r
+        return\r
+    else:\r
+        print("Temps maximum Tmax= ", tmax, " atteint")\r
+        return\r
+\r
+def solve( my_mesh,filename, resolution):\r
+    print("Resolution of the Isothermal Euler system in dimension 2 on "+str(my_mesh.getNumberOfCells())+ " cells")\r
+    print("Initial data : ", "Riemann problem")\r
+    print("Boundary conditions : ", "Neumann")\r
+    print("Mesh name : ",filename )\r
+    # Problem data\r
+    tmax = 10.\r
+    ntmax = 10\r
+    cfl=1\r
+    output_freq = 1\r
+    EulerSystemStaggered(ntmax, tmax, cfl, output_freq, my_mesh, filename)\r
+    return\r
+\r
+if __name__ == """__main__""":\r
+    if len(sys.argv) >1 :\r
+        filename=sys.argv[1]\r
+        my_mesh = cdmath.Mesh(filename)\r
+    else :\r
+        filename = "CartesianGrid"\r
+        ax=0;bx=1;nx=20;\r
+        ay=0;by=1;ny=10;        \r
+        my_mesh = cdmath.Mesh(ax,bx,nx,ay,by,ny)\r
+\r
+    solve(my_mesh,filename,100)\r