doc/tutorial/atestMEDCouplingNumPy.rst

   1
   2 .. _python_testMEDCouplingNumPy_solution:
   3
   4 Playing with NumPy and SciPy
   5 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   6
   7 ::
   8
   9         import MEDCoupling as mc
  10
  11         #
  12         # NumPy
  13         #
  14         import numpy as np
  15
  16         # Checking NumPy binding
  17         assert(mc.MEDCouplingHasNumPyBindings())
  18         # Playing with conversion and shared data
  19         arr = mc.DataArrayDouble(12)
  20         arr[:] = 4.
  21         nparr = arr.toNumPyArray()
  22         print nparr.__repr__()
  23         print nparr.tolist()
  24         nparr[::2] = 7.
  25         print nparr.__repr__()
  26         print arr.__repr__()
  27         del arr
  28         import gc; gc.collect()     # Make sure the object has been deleted
  29         print nparr.__repr__()
  30         arr2 = mc.DataArrayDouble(nparr)
  31         print arr2.__repr__()
  32         nparr[:] = 5.
  33         print nparr.__repr__()
  34         print arr2.__repr__()
  35         # Writing to file
  36         f = open("toto.data","w+b")
  37         a = np.memmap(f,dtype='float64',mode='w+',offset=0,shape=nparr.shape)
  38         a[:] = nparr[:]
  39         f.flush()
  40         # Re-reading file
  41         f2 = open("toto.data","r+b")
  42         b = np.memmap(f2,dtype='float64',mode='r',offset=0,shape=(12,))
  43         a[:] = 3.14
  44         f.flush()
  45         b = np.memmap(f2,dtype='float64',mode='r',offset=0,shape=(12,))
  46         print b.__repr__()
  47         #
  48         # SciPy
  49         #
  50         assert(mc.MEDCouplingHasSciPyBindings())
  51         c1 = mc.MEDCouplingCMesh()
  52         arr1 = mc.DataArrayDouble(7)
  53         arr1.iota()
  54         c1.setCoords(arr1,arr1,arr1)
  55         c2 = mc.MEDCouplingCMesh()
  56         arr2 = mc.DataArrayDouble(9)
  57         arr2.iota()
  58         arr2 *= 6./8.
  59         c2.setCoords(arr2,arr2,arr2)
  60         c1 = c1.buildUnstructured()
  61         c2 = c2.buildUnstructured()
  62         c2.translate([6.,0.,0.])
  63         c = mc.MEDCouplingUMesh.MergeUMeshes([c1,c2])
  64         c.mergeNodes(1e-12)
  65         skinAndNCFaces = c.computeSkin()
  66         skinAndNCFaces.zipCoords()
  67         # Isolating non conform cells
  68         from MEDCouplingRemapper import MEDCouplingRemapper
  69         rem = MEDCouplingRemapper()
  70         rem.setMaxDistance3DSurfIntersect(1e-12)
  71         rem.setMinDotBtwPlane3DSurfIntersect(0.99)
  72         rem.prepare(skinAndNCFaces,skinAndNCFaces,"P0P0")
  73         mat = rem.getCrudeCSRMatrix()
  74         indptr = mc.DataArrayInt(mat.indptr)
  75         indptr2 = indptr.deltaShiftIndex()
  76         cellIdsOfSkin = indptr2.getIdsEqual(1)
  77         skin = skinAndNCFaces[cellIdsOfSkin]
  78         skin.writeVTK("skin.vtu")