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[Solve]programming issue

Hi,

I think it's quite trivial, but I spent time on finding how to get a float as argument for an application.

It's a little application dealing with boundary conditions, let's name it JulienFoam

I want to be able to use it as:
JulienFoam <Boundary> -numericalarg <float>

for the moment, I have that:

int main(int argc, char *argv[])
{
float numericalarg;
argList::validArgs.append("patchName");
argList::validOptions.insert("numericalarg",numeri calarg);

word patchName(args.args()[1]);

[...]

}

and I don't find how to get my numericalarg as a float, it seems that argList only gets strings.

If someone can give me any piece of advice, I think it would be very usefull for my future using, not just for that program.

Regards

Julien

Julien,

yes, arguments are passed only as strings.

Have a look into fluentMeshToFoam.L where it says:

Code:

    scalar scaleFactor = 1.0;

    if (args.options().found("scale"))

    {

        scaleFactor = atof(args.options()["scale"].c_str());

    }

Henrik

Perfect, that is exactly what I was looking for! I looked over other applications but not that one.

Thanks a lot!

Just for completeness (to followup on what Henrik mentioned), you might note that readScalar operates on an Istream, and IStringStream can be used to create an Istream from a string.
Thus the following would also work:

Code:

if (args.options().found("scale"))

{

    scaleFactor = readScalar(IStringStream(args.options()["scale"])());

}

The extra '()' on the IStringStream constructor casts away constness.

Of course, both solutions look fairly messy.

In OpenFOAM-1.6, the same thing becomes much more convenient:

Code:

    scalar scaleFactor = 1.0;

    args.optionReadIfPresent("scale", scaleFactor);