calc_rotation_matrix

stcal.alignment.calc_rotation_matrix(roll_ref: float, v3i_yangle: float, vparity: int = 1) → list[float][source]

Calculate the rotation matrix.

Parameters:

  • roll_ref (float) – Telescope roll angle of V3 North over East at the ref. point in radians

  • v3i_yangle (float) – The angle between ideal Y-axis and V3 in radians.

  • vparity (int) – The x-axis parity, usually taken from the JWST SIAF parameter VIdlParity. Value should be “1” or “-1”.

Returns:

matrix – A list containing the rotation matrix elements in column order.

Return type:

list

Notes

The rotation matrix is

\[\begin{split}PC = \\begin{bmatrix} pc_{1,1} & pc_{2,1} \\\\ pc_{1,2} & pc_{2,2} \\end{bmatrix}\end{split}\]