Clear row/column of a sparse matrix

Submitted by Christopher Batty

Assigned to Nobody

Link to original bugzilla bug (#273)

Description

Clearing a row or column of a matrix (depending on the storage format) can sometimes be a useful operation in finite element/difference computations, such as in setting up Dirichlet boundary conditions. Using this method, you can build your matrix without regard for boundary conditions, and then in a second step replace the rows corresponding to known values with the identity.

PETSC, for example, supports this operation with the MatZeroRows command.