* \n This method makes the assumption that \a this field is correctly defined when this method is called (\a this->checkConsistencyLight() returns without any exception thrown), **no check of this will be done**.
* \n This method returns a restriction of \a this so that only tuple ids specified in [ \a partBg , \a partEnd ) will be contained in the returned field.
* \n Parameter [\a partBg, \a partEnd ) specifies **cell ids whatever the spatial discretization** of \a this (
* \n This method makes the assumption that \a this field is correctly defined when this method is called (\a this->checkConsistencyLight() returns without any exception thrown), **no check of this will be done**.
* \n This method returns a restriction of \a this so that only tuple ids specified in [ \a partBg , \a partEnd ) will be contained in the returned field.
* \n Parameter [\a partBg, \a partEnd ) specifies **cell ids whatever the spatial discretization** of \a this (