[celestial]

Good evening

I want to assign A and b in Ax=b where x is my scalar field:


fvScalarMatrix xEqn
(
fvm::ddt(x) + ......
) ;

xEqn.internalCoeffs()[patchid]= whatever;

xEqn.boundaryCoeffs()[patchid]= whatever;

xEqn.solve();



I could not run the program without getting a complaint about patch type and constraint type required under file 0/x. i.e., I had to add something like

boundaryField
{
patchname
{
type mixed;
valueFraction uniform 0.0;
refValue uniform 0.0;
refGradient uniform 0.0;
}


in that file 0/x

I chose mixed because it seems to be the most general generic boundary condition in OpenFOAM.

It would have been nice if the dictionary had not been required and I hope that my above addition to 0/x does not nullify the above assignment in my program.

Any comments welcome

[celestial]

The good news is that adding

forAll(patchname, i)
{

Info<< " intCoeff = "
<< xEqn.internalCoeffs()[patchid][i] << " bndCoeff = "
<< xEqn.boundaryCoeffs()[patchid][i] << " s\n" << endl;

}

after the 3 lines

xEqn.internalCoeffs()[patchid]= bigfixednumber1;

xEqn.boundaryCoeffs()[patchid]= bigfixednumber2;

xEqn.solve();


clearly indicates that the above values are not modified by the dictionary



boundaryField
{
patchname
{
type mixed;
valueFraction uniform 0.0;
refValue uniform 0.0;
refGradient uniform 0.0;
}


in file 0/x