Hi,

I would like to define a square matrix-free operator which dimension corresponds to the size of the restricted space that corresponds to the left boundary of the 2d domain. So basically the operator behaves as:

another_vector_on_1D_space = matrix_on_1D_space * input_vector_on_1D_space

vector_on_2D_space = prolongation_matrix * another_vector_on_1D_space

another_vector_on_2D_space = matrix_on_2D_space * vector_on_2D_space

return_vector_on_1D_space = restrictionMatrix * another_vector_on_2D_space

I started to implement this in the following script: meshL_2d_SLEPc.edp (1.5 KB)

Obviously there is something I do not understand, I guess I have non consistent operator sizes.

Could someone please help me here ?

Best,

Lucas

PS: It is not clear to me why A.n is different from Vh.ndof. Could someone please explain me why?