pyswice_ck_utilities

pyswice_ck_utilities.ckRead(time, spacecraft_id=-62, reference_frame='J2000')[source]

Purpose: Read information out of a CK Kernel for a single instance and returns a quaternion array and an angular velocity array

Warning

Assumes that SCLK and CK kernels are already loaded using furnsh because pyswice gets mad when loading the same files over and over again.

Parameters:

  • time – Should be in UTC Gregorian, and passed in as a string, ex: ‘FEB 01,2021 14:00:55.9999 (UTC)’

  • spacecraft_id – Spacecraft ID – Default: -62

  • reference_frame – is a character string which specifies the, reference frame of the segment. Reference Frame, ex: “J2000”

Returns:

None

pyswice_ck_utilities.ckWrite(handle, time, mrp_array, av_array, start_seg, spacecraft_id=-62, reference_frame='J2000')[source]

Purpose: Creates a CK kernel from a time_array, mrp_array, and an av_array. Assumes that the SCLK is furnshed

Warning

time stamps for the time_array, mrp_array, and av_array must line up exactly!!

Parameters:

  • handle – What you would like the CK file to be named. Note, it must be in double quotes and end in .bc, ex: “moikernel.bc”

  • time – numpy array of time stamps in nanoseconds

  • mrp_array – array of modified Rodriguez parameters in column order x, y, z

  • av_array – array of angular velocities about 3 axis in column order x, y, z

  • start_seg – the SCLK time that the file begins at in UTC Gregorian ex: ‘FEB 01,2021 12:00:55.9999 (UTC)’

  • spacecraft_id – spacecraft ID ex:-62

  • reference_frame – reference frame ex:”J2000”

Returns: