how to extract sparse matrix from assembled form

Question

In Fenics 1.5.0, 'uBLAS' is no longer supported. What can I do to extract a sparse array that represents an assembled form?

More detailed, setting

dolfin.parameters.linear_algebra_backend = "Eigen"

the command that worked for "uBLAS"

rows, cols, values = A.data()

fails with AttributeError: 'Matrix' object has no attribute 'data'

What is the command or the backend to use here?

Answer 1

Use:

as_backend_type(A).data()

or

as_backend_type(A).sparray()