A list of scalar names for the dataset. This makes
        sure to put the active scalar's name first in the list.

def scalar_names(self):
        """A list of scalar names for the dataset. This makes
        sure to put the active scalar's name first in the list."""
        names = []
        for i in range(self.GetPointData().GetNumberOfArrays()):
            names.append(self.GetPointData().GetArrayName(i))
        for i in range(self.GetCellData().GetNumberOfArrays()):
            names.append(self.GetCellData().GetArrayName(i))
        try:
            names.remove(self.active_scalar_name)
            names.insert(0, self.active_scalar_name)
        except ValueError:
            pass
        return names