python - What does the mth argument to RectBivariateSpline do in old (0.9.0) versions of scipy -

i'm stuck using scipy version 0.9.0.

in version scipy.interpolate.rectbivariatespline.__call__ has keword argument mth. other default value (mth='array'), can't tell how used, in particular other options (if any) supported , do?

the documentation have found more date versions, mth argument deprecated (in favor of grid argument). not useful me.

there no other option available:

here's source code function:

def __call__(self, x, y, mth='array'):     """ evaluate spline @ positions x,y."""     x = np.asarray(x)     y = np.asarray(y)     # empty input yields empty output     if (x.size == 0) , (y.size == 0):         return array([])      if mth=='array':         tx,ty,c = self.tck[:3]         kx,ky = self.degrees         z,ier = dfitpack.bispev(tx,ty,c,kx,ky,x,y)         assert ier==0,'invalid input: ier='+`ier`         return z     raise notimplementederror('unknown method mth=%s' % mth)