def f_lon(self, function, psi, lon): MathOperations.f_lon(function, psi, lon):
def f_lon(self, function, psi, lon): self.result = MathOperations.f_lon(function, psi, lon)
def f_lon(self, function, psi, lon): self.result = MathOperations.f_lon(function, psi, lon)