3D interpolation Qhull error

[browniea]

Using Interp.griddata ran into a Qhull error when interpolating. This code seemed to fix the issue:

        bad = ~np.isfinite(sigma) | (np.abs(sigma) > 1e6)
        if bad.any():
            sigma[bad] = -1.0
            _ds["mesh2d_interface_sigma"] = xr.DataArray(
                sigma,
                dims=_ds["mesh2d_interface_sigma"].dims,
                attrs=_ds["mesh2d_interface_sigma"].attrs,
            )

[browniea]

I'm investigating this further, I'll plan to add a fix to PR #432