# SystemAssembler¶

class dolfin.cpp.fem.SystemAssembler(a, L, bcs)

This class provides an assembler for systems of the form Ax = b. It differs from the default DOLFIN assembler in that it applies boundary conditions at the time of assembly, which preserves any symmetries in A.

Constructor

assemble()

• assemble(A, b)

Assemble system (A, b)

• assemble(A)

Assemble matrix A

• assemble(b)

Assemble vector b

• assemble(A, b, x0)

Assemble system (A, b) for (negative) increment dx, where x = x0 - dx is solution to system a == -L subject to bcs. Suitable for use inside a (quasi-)Newton solver.

• assemble(b, x0)

Assemble rhs vector b for (negative) increment dx, where x = x0 - dx is solution to system a == -L subject to bcs. Suitable for use inside a (quasi-)Newton solver.

thisown

The membership flag