IterativeNonlinearLSTSQwBackground.compute_jacobian_bg

giant.point_spread_functions.psf_meta:

static IterativeNonlinearLSTSQwBackground.compute_jacobian_bg(x, y)

This computes the Jacobian matrix for the background terms.

Mathematically this is

\[\mathbf{J}_{bg} = \left[\begin{array}{ccc}\frac{\partial f_{bg}(x,y)}{\partial B} & \frac{\partial f_{bg}(x,y)}{\partial C} & \frac{\partial f_{bg}(x,y)}{\partial D}\end{array}\right]= \left[\begin{array}{ccc} x & y & 1\end{array}\right]\]

The results from this function should be appended to the rest of the Jacobian matrix using hstack.

Parameters:

• x (ndarray) – The x values underlying the data the surface is to be fit to

• y (ndarray) – The y values underlying the data the surface is to be fit to

Returns:

The Jacobian for the background as a nx3 numpy array

Return type:

ndarray