BCsubs - Substitute boundary conditions in partially integrated variational forms
Calling sequence:
BCsubs(bclist,expr):
Parameters
bclist - A list of equalities specifying boundary conditions. The left hand sides must be either variables, or derivatives of variables, appearing inside BoundaryInt() in expr.
expr - An expression containing BoundaryInt()s, typically as a result of using partInt.
Synopsis:
Examples:
> femform:=0=partInt(ElementInt(test(x)*diff(v(x),x,x)),v(x));
/d \ /d \
femform := 0 = -ElementInt(|-- v(x)| |-- test(x)|)
\dx / \dx /
/d \
+ BoundaryInt(BdNx |-- v(x)| test(x))
\dx /
> BCsubs([diff(v(x),x)=q],femform);
/d \ /d \
0 = -ElementInt(|-- v(x)| |-- test(x)|) + BoundaryInt(BdNx q test(x))
\dx / \dx /