;+ ; NAME: ; ADJUST_DATE_OBS ; ; PURPOSE: ; This function returns a structure of two string elements containing the ; adjusted date-obs and time-obs for a given C1, C2, or C3 image header. ; c2_time_offsets.dat file is used to get the time offset using first ; value extend, interpolation, or last value extend. It then calculates ; the corrected date-obs and time-obs and returns them. ; ; CATEGORY: ; LASCO DATA_ANAL ; ; CALLING SEQUENCE: ; adj = adjust_date_obs(hdr) ; ; INPUTS: ; hdr: A C1, C2, or C3 image header ; ; OPTIONAL INPUTS: ; verbose: print diagnostic messages. ; adj = adjust_date_obs(hdr,/verbose) ; ; OUTPUTS: ; A two element structure of DATE and TIME containing the adjusted ; DATE_OBS and TIME_OBS. ; ; Example: ; hdr.DATE_OBS = '1998/01/01' ; hdr.TIME_OBS = '00:10:11.181' ; ; adj = adjust_date_obs(hdr) ; ; adj.DATE = '1998/01/01' ; adj.TIME = '00:13:06.590' ; ; ; MODIFICATION HISTORY: ; Written by: Ed Esfandiari, Feb 1999 ; 7/24/00, nbr - Add SCCS version, reduce_history commmon block ; 11. 6.01, nbr - Use OPENR instead of OPENU ; 11.30.01, nbr - Change fnm for windows SSW compatibility ; 7. 5.02, nbr - Fix SCCS version syntax ; 09/22/05 Ed Esfandiari - Check hhdr and if time_obs='' assume level-1 ; file and do not adjust date_time (already adjusted). ; ; ; @(#)adjust_date_obs.pro 1.9, 09/13/10 - NRL LASCO IDL LIBRARY ; ;- function get_offset,utime,verbose ;fnm= 'c2_time_offsets.dat' ;fnm= GETENV('NRL_LIB')+'/lasco/data_anal/data/'+'c2_time_offsets.dat' fnm= GETENV('NRL_LIB')+'/idl/data_anal/data/'+'c2_time_offsets.dat' OPENR,lu,fnm,/GET_LUN mjd=0L time=0L xpos= 0.0 moved= 0.0 offset= 0.0 tmp= '' sutime= strtrim(string(utime.mjd)+string(utime.time,'(i8.8)'),2) found= -1 READF,lu,tmp READF,lu,tmp READF,lu,mjd,time,xpos,moved,offset mjd1= mjd & time1= time & offset1= offset smjd= strtrim(string(mjd)+string(time,'(i8.8)'),2) if(smjd ge sutime) then found= -2 if(found eq -2) then begin mjd2=mjd1 & time2=time1 & offset2= offset1 offset= offset2 READF,lu,mjd1,time1,xpos,moved,offset1 end while (not eof(lu) and found eq -1) do begin READF,lu,mjd,time,xpos,moved,offset mjd2=mjd1 & time2=time1 & offset2= offset1 mjd1= mjd & time1= time & offset1= offset smjd= strtrim(string(mjd)+string(time,'(i8.8)'),2) if(smjd ge sutime) then found= 1 end CLOSE,lu FREE_LUN,lu if(KEYWORD_SET(verbose)) then begin print,'' print,'Calculate offset for: ',utime.mjd,utime.time print,'Following times and offsets will be used:' print,mjd2,time2,offset2 print,mjd1,time1,offset1 print,'' end if(found lt 0) then begin if(found eq -2) then begin if(KEYWORD_SET(verbose)) then begin print,'Header date is earlier than c2_time_offset.dat dates. Will use the' print,'first offset from c2_time_offset.dat instead of extrapolating.' end endif else begin if(KEYWORD_SET(verbose)) then begin print,'Header date is beyond c2_time_offset.dat dates. Will use the last' print,'offset from c2_time_offset.dat instead of extrapolating.' end endelse endif else begin if(offset1 ne offset2) then begin ;interpolate if(KEYWORD_SET(verbose)) then print,'interpolating ...' days= mjd1 - mjd2 x2= long(time2) x1= long(days*86400000L + time1) s= double((offset1 - offset2)/(x1 - x2)) days1= utime.mjd - mjd2 x= long(days1*86400000L + utime.time) offset= s * (x - x2) + offset2 end endelse if(KEYWORD_SET(verbose)) then print,'Calculated offset (sec)= ',offset return,offset end function adjust_date_obs,hdr,verbose=verbose COMMON reduce_history, cmnver, prev_a, prev_hdr, zblocks0 version= '@(#)adjust_date_obs.pro 1.9, 09/13/10' ; LASCO IDL LIBRARY ; cmnver = strmid(version,4,strlen(version)) adj= {date:'', time:''} ; Note: the CRPIX1 should be overwritten by the x_val (i.e. 512.28 for C2)?? shdr= hdr IF (DATATYPE(shdr) NE 'STC') THEN shdr=LASCO_FITSHDR2STRUCT(hdr) tel= strupcase(STRTRIM(shdr.detector,2)) date= shdr.date_obs time= STRTRIM(shdr.time_obs,2) ; Level-1 headers (and higher) are already adjusted for date and time. For these files, ; Unlike level-0.5 files, shdr.date_obs is set to 'yyyy-mm-ddThh:mm:ss.msc' and shdr.date ; is set to ''. So check the shdr.time and if it is blank assume it is a level-1 hdr which ; does not need time correction: IF (time EQ '') THEN BEGIN adj.date= STRMID(date,0,4)+'/'+STRMID(date,5,2)+'/'+STRMID(date,8,2) ;=>yyyy/mm/dd adj.time= STRMID(date,11,12) IF (KEYWORD_SET(verbose)) THEN PRINT,'level-1 hdr input: '+date +' not adjusted' return, adj ENDIF ; Get number of sec/pix for this image to calculate the offset from ; the orbit files (xx= ~60 arcmin): ;xx= ...... ;spp= 86400.0 / (xx * 5) ;Assume sun moves by 1 degree (60 arcmin) per day, for now, so xx= 60: ;spp= 86400.0 / (60.0 * 5) ;offset= (sun_cen.xcen - x_val) * spp ; offset in seconds utctime= STR2UTC(date+' '+time) offset= get_offset(utctime,verbose) ; Subtrct the offset (changed to msec) from the date/time_obs after ; converting them to utc format: utctime.time= utctime.time - (offset*1000.0) if(utctime.time lt 0L) then begin utctime.mjd= utctime.mjd - 1L utctime.time= utctime.time + 86400000L end if(utctime.time ge 86400000L) then begin utctime.mjd= utctime.mjd + 1L utctime.time= utctime.time - 86400000L end ; Change from utc format to string of form "yyyy-mm-ddThh:mm:ss.mmmZ" ; and pick up new date/time: stime= utc2str(utctime) new_date= strmid(stime,0,4)+'/'+strmid(stime,5,2)+'/'+strmid(stime,8,2) new_time= strmid(stime,11,12) if(KEYWORD_SET(verbose)) then begin print,'' print,'Camera= ',tel print,'Original date/time: ',shdr.date_obs,' ',shdr.time_obs print,'Adjusted date/time: ',new_date,' ',new_time print,'' end adj.date= new_date adj.time= new_time return,adj end