Allow L = 0 in solve

Registered by Anders Logg

Add check in solve() function (but not in LinearVariationalProblem) to allow

a = dot(grad(u),grad(v)*dx
L = 0
...
solve(a==L, u, bc)

Blueprint information

Status:
Complete
Approver:
None
Priority:
Low
Drafter:
None
Direction:
Needs approval
Assignee:
None
Definition:
Obsolete
Series goal:
Accepted for 1.1.x
Implementation:
Unknown
Milestone target:
None
Completed by
Garth Wells

Whiteboard

MSA: This is not solvable in UFL because the zero rhs form is not currently representable in pure UFL, and UFL cannot create a zero valued dolfin Constant. However ufl.Equation does not check the type of its rhs, so dolfin is free to handle this by checking the number of arguments of lhs (1 argument means F == 0, 2 arguments means a == 0).

(?)

Work Items

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