Arun, > Can someone tell me how to use shape_grad() to the get the gradient in > only a particular direction ? Using tutorial programs I figured out how > to get the derivative of the shape function for individual components > but unsure how to use shape_grad() to get the derivative in a particular > direction (say Ux + Uy - Vz with U and V being the two components).
fe_values.shape_grad (i,q) returns the gradient of shape function i and quadrature point q, i.e. all components of the vector. If you are in 3d, then fe_values.shape_grad(i,q)[0] is the X-derivative (in real coordinates, not the reference coordinates of the cell) and fe_values.shape_grad(i,q)[1] fe_values.shape_grad(i,q)[2] similarly for the y and z derivatives. Best W. ------------------------------------------------------------------------- Wolfgang Bangerth email: [email protected] www: http://www.math.tamu.edu/~bangerth/ _______________________________________________ dealii mailing list http://poisson.dealii.org/mailman/listinfo/dealii
