procedure: thm_cal_fgm_spin_harmonics Purpose: Uses spin harmonic corrections from calibration files to fix spin harmonic errors in fgm data. The correction values are subtracted from the fgm data. These values are downloaded from files in the data/themis/th?/l1/fgm/0000/spin_cal/ directory. Inputs: times: An N-length array of times matching the spinphase data and the fgmdata, in double precision seconds since 1970. spinphase: An N-length array of spinphase data in degrees. fgmdata: An Nx3 length array of fgm data in nT. fgmdata[*,0] = x,fgmdata[*,1] = y,fgmdata[*,2] = z probe: The probe letter, as a string. shadows:A struct with shadow start and stop times retrieved from the new spinmodel. {start:shadow_starts,stop:shadow_stops} Outputs: Mutates fgmdata in place. error: Set to 1 if error occurs, 0 otherwise Notes: 1. Specifically, this corrects errors due to the solar array current. Thus it is only applied when the spacecraft is not in shadow. 2. The correction should largely remove the 1 Hz and .66 Hz harmonics from the X & Y components of the data and it should remove the .66 Hz and .33 Hz harmonics from the Z component of the data.(in DSL coordinates) 3. The .33 Hz harmonic of the X & Y components should remain. There should be no 1 Hz Harmonic in the Z-component 4. If a calibration file is not found it will use a default calibration file. This file will be the calibration file for the probe that corresponds to the latest month. This could be an issue for dates very early in the mission, as there are no calibration files for these dates, but they are not temporally close to the default calibration values. $LastChangedBy: aaflores $ $LastChangedDate: 2012-02-22 11:30:33 -0800 (Wed, 22 Feb 2012) $ $LastChangedRevision: 9811 $ $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/trunk/projects/themis/spacecraft/fields/thm_cal_fgm_spin_harmonics.pro $