;+ ; NAME: ; GETPARMS ; PURPOSE: ; Routine to read GCAL files (offsets and gain parameters) and return ; the appropriate values for a given date and time ; CATEGORY: ; OVRO APC UTILITY ; CALLING SEQUENCE: ; gparm = getparms(tls) ; INPUTS: ; tls A standard time/label structure giving the date and time for ; which the parameters are desired. ; OPTIONAL (KEYWORD) INPUT PARAMETERS: ; ROUTINES CALLED: ; break_file ; OUTPUTS: ; gparm A structure containing the offsets and gain parameters. If ; there was a problem finding or reading the files, GAINPARM ; will contain nominal values (offsets all zero, nonlinearity ; zero, and unit attenuation factors), and the epoch will have ; day number set to zero. ; Structure contents: ; {gparm, epoch: strarr(2) ; Each of length 17, YYYY.DDD HH:MM:SS ; poffsets: ptr to fltarr(NANT^2) ; Array of offsets, one for each chan ; pgnp: ptr to NANT-element array of structures as follows ; {gnp,nlparm: float ; Nonlinearity parameter ; attn: fltarr(3) ; Attenuation factor ; ndfac: float ; ND_eff factor (relative to 500) ; resid: float ; Residual indicating quality of GCAL ; } ; dlcal: fltarr(4,14) ; To hold Delay line calibration ; pgcal: ptr to NANT-element x NF-element array with GCAL results ; {gcal, rcvr: float ; Receiver IF level ; nd: float ; Noise Diode increment ; resid: float ; RMS difference of model to data ; } ; } ; COMMENTS: ; SIDE EFFECTS: ; RESTRICTIONS: ; Contains code specific to 5 antennas. ; MODIFICATION HISTORY: ; Written 23-Aug-1998 by Dale E. Gary ; 05-Sep-1998 DG ; Made the GPARM structure a named structure. ; 26-Nov-1999 DG ; Changed to return a new form of GPARM structure (introduced due ; to creation of GAINPARM segment). ;- function getline,files,nfiles,tls ; Helper function to search through a list of files and return the line ; that is the next earlier one in time to the time given by tls ; Error return if no files if (nfiles eq 0) then return,-1 ; Get the expected file name root (e.g. 199808) from year and month ; of today's date. ymd = cvdoy(tls.year,tls.day) yrmon = string(ymd(0:1),format='(I4,I2.2)') ; Sort the file names into date order files = files(sort(files)) find: ; Find the filename that matches YRMON, or is the next earlier one for i = 0, nfiles-1 do begin filename = files(i) break_file,filename,disk,direc,root,ext if (root eq yrmon) then begin ; We have an exact match, so go with it goto,done endif else if (root gt yrmon) then begin ; We found a file later than the one we want, so ; take the next earlier one, if any if (i eq 0) then begin ; This was the earliest file, and is too late, so return ; an error (-1) to indicate failure return,-1 endif filename = files(i-1) goto,done endif ; No file yet, so keep going endfor done: ; The filename is either the correct date or the next earlier one ; Now search through the entries to find the best date within the file ON_IOERROR,err_rtn openr,lun,/get_lun,filename ; Read and discard the header lines hedlines = strarr(3) readf,lun,hedlines today = tls.yrday+tls.timstr prevline = (line = '') while (not EOF(lun)) do begin readf,lun,line reads,line,timstr,format='(A17)' if (timstr eq today) then begin ; We have an exact match, so go with it free_lun,lun return,line endif else if (timstr gt today) then begin ; We found a time later than the one we want, so ; take the next earlier one, if any if (prevline eq '') then begin ; This was the earliest line, and is too late, so we have to go back ; to an earlier file! ; Subtract one month from YRMON yrmon = string(long(yrmon)-1,format='(i6)') ; Handle case of month of January by subtracting one year ; and adding 12 months if (strmid(yrmon,4,2) eq '00') then begin yrmon = string(long(yrmon)-100,format='(i6)') ; Subtract year strput,yrmon,'12',4 ; Replace month w/ 12 endif free_lun,lun ; Go back to find the next earlier file goto,find endif else begin free_lun,lun return,prevline endelse endif ; No match yet, so keep going prevline = line endwhile free_lun,lun ; We reached the end of the file without a match, but the last line must ; be the right one, so if it is not empty then return it if (line eq '') then return,-1 $ else return,line err_rtn: ; Return code for file read error return,-2 end function getparms,tls ; Find all potential offsets files in the DATABASE directory (DBDIR) offiles = findfile(!defaults.dbdir+'*.off',count=noff) ; Find all potential gain parameter files in the DATABASE directory (DBDIR) gnfiles = findfile(!defaults.dbdir+'*.gnp',count=ngnp) ; This will have to be made general for different numbers of antennas ; Declare storage for the offsets offsets = fltarr(25) gnp = replicate({gnp},5) ; Get the offsets file entry that is the next earlier time with respect to TLS ; using the GETLINE routine above. line = getline(offiles,noff,tls) offepoch = {epoch} ; Check the variable type of LINE. It should be 7 (i.e. a string), so if ; not then GETLINE() returned an error. if ((size(line))(1) ne 7) then begin if (line eq -1) then begin errstr = 'GETPARMS: Channel offsets file not found. Will use 0 for all.' IF (keyword_set(cmdfile)) THEN printf,msglun,errstr,format='(a)' $ ELSE ans = widget_message(errstr,/ERROR) endif else begin errstr = 'GETPARMS: Error reading channel offsets file. Will use 0 for all.' IF (keyword_set(cmdfile)) THEN printf,msglun,errstr,format='(a)' $ ELSE ans = widget_message(errstr,/ERROR) endelse ; Flag epoch as current year but ZERO day number offepoch.yr = tls.year offepoch.doy = 0 offepoch.sec = 0 endif else begin reads,line,offsets,format='(17X,25F5.1)' offepoch.yr = strmid(line,0,4) offepoch.doy = strmid(line,5,3) offepoch.sec = long(strmid(line,9,2)*3600L+strmid(line,12,2)*60L+strmid(line,15,2)) endelse ; Get the gain parameter file entry that is the next earlier time with respect to TLS ; using the GETLINE routine above. line = getline(gnfiles,ngnp,tls) ; Check the variable type of LINE. It should be 7 (i.e. a string), so if ; not then GETLINE() returned an error. if ((size(line))(1) ne 7) then begin if (line eq -1) then begin errstr = 'GETPARMS: Gain parm file not found. Will use nominal values.' IF (keyword_set(cmdfile)) THEN printf,msglun,errstr,format='(a)' $ ELSE ans = widget_message(errstr,/ERROR) endif else begin errstr = 'GETPARMS: Error reading gain parm file. Will use nominal values.' IF (keyword_set(cmdfile)) THEN printf,msglun,errstr,format='(a)' $ ELSE ans = widget_message(errstr,/ERROR) endelse ; Flag epoch as current year but ZERO day number gnpepoch = string(tls.year,format='(I4,".000 00:00:00")') endif else begin reads,strmid(line,17,strlen(line)-17),gnp gnpepoch = strmid(line,0,17) endelse ; Convert offsets to a square, 8x8 array to match the new form of offsets. Since ; the offsets are in a fixed format, just hardwire the conversion ibl = [ 0, 6, 8,10,12 ,$ 5, 1,14,16,18 ,$ 7,13, 2,20,22 ,$ 9,15,19, 3,24 ,$ 11,17,21,23, 4 ] offsetsq = fltarr(8,8) + !values.f_nan for j = 0, 4 do begin for i = 0, 4 do begin offsetsq[i,j] = offsets[ibl[j*5 + i]] endfor endfor gparm = {epoch:offepoch,poffsets:ptr_new(offsetsq),pgnp:ptr_new(gnp),$ dlcal:fltarr(4,14),pgcal:ptr_new(0)} return,gparm end