compute_roll_ref

jwst.assign_wcs.pointing.compute_roll_ref(v2_ref, v3_ref, roll_ref, ra_ref, dec_ref, new_v2_ref, new_v3_ref)[source]

Computes the position of V3 (measured N to E) at the center af an aperture.

Parameters:
  • v3_ref (v2_ref,) – Reference point in the V2, V3 frame [in arcsec] (FITS keywords V2_REF and V3_REF)
  • roll_ref (float) – Position angle of V3 at V2_REF, V3_REF, [in deg] When ROLL_REF == PA_V3, then (V2_REF, V3_REF) = (0, 0)
  • dec_ref (ra_ref,) – RA and DEC corresponding to V2_REF and V3_REF, [in deg]
  • new_v3_ref (new_v2_ref,) – The new position in V2, V3 where the position of V3 is computed, [in arcsec] The center of the aperture in V2,V3
Returns:

new_roll – The value of ROLL_REF (in deg)
Return type:

float