PROCEDURE: get_thc_peir PURPOSE: Returns peir data structure at a single time from common generated by thm_load_esa_pkt.pro INPUT: time: dbl time of data to be returned KEYWORDS: start: 0,1 if set, gets first time in common block en: 0,1 if set, gets last time in common block advance 0,1 if set, gets next time in common block retreat 0,1 if set, gets previous time in common block index long gets data at the index value "ind" in common block calib: 0,1 not working yet, allows alternate calibration times 0,1 returns an array of times for all the data, returns 0 if no data CREATED BY: J. McFadden VERSION: 1 LAST MODIFICATION: 07/03/22 MOD HISTORY: NOTES: Data structures can be used as inputs to functions such as n_3d.pro, v_3d.pro Or used in conjunction with iterative programs such as get_3dt.pro, get_en_spec.pro