pro readcol,name,v1,v2,v3,v4,v5,v6,v7,v8,v9,v10,v11,v12,v13,v14,v15, $ v16,v17,v18,v19,v20,v21,v22,v23,v24,v25, COMMENT = comment, $ FORMAT = fmt, DEBUG=debug, SILENT=silent, SKIPLINE = skipline, $ NUMLINE = numline, DELIMITER = delimiter, NAN = NaN, $ PRESERVE_NULL = preserve_null ;+ ; NAME: ; READCOL ; PURPOSE: ; Read a free-format ASCII file with columns of data into IDL vectors ; EXPLANATION: ; Lines of data not meeting the specified format (e.g. comments) are ; ignored. Columns may be separated by commas or spaces. ; ; Use READFMT to read a fixed-format ASCII file. Use RDFLOAT for ; much faster I/O (but less flexibility). Use FORPRINT to write ; columns of data (inverse of READCOL). ; ; CALLING SEQUENCE: ; READCOL, name, v1, [ v2, v3, v4, v5, ... v25 , COMMENT=, /NAN ; DELIMITER= ,FORMAT = , /DEBUG , /SILENT , SKIPLINE = , NUMLINE = ] ; ; INPUTS: ; NAME - Name of ASCII data file, scalar string. ; ; OPTIONAL INPUT KEYWORDS: ; FORMAT - scalar string containing a letter specifying an IDL type ; for each column of data to be read. Allowed letters are ; A - string data, B - byte, D - double precision, F- floating ; point, I - integer, L - longword, Z - longword hexadecimal, ; and X - skip a column. ; ; Columns without a specified format are assumed to be floating ; point. Examples of valid values of FMT are ; ; 'A,B,I' ;First column to read as a character string, then ; 1 column of byte data, 1 column integer data ; 'L,L,L,L' ;Four columns will be read as longword arrays. ; ' ' ;All columns are floating point ; ; If a FORMAT keyword string is not supplied, then all columns are ; assumed to be floating point. ; ; /SILENT - Normally, READCOL will display each line that it skips over. ; If SILENT is set and non-zero then these messages will be ; suppressed. ; /DEBUG - If this keyword is non-zero, then additional information is ; printed as READCOL attempts to read and interpret the file. ; COMMENT - single character specifying comment character. Any line ; beginning with this character will be skipped. Default is ; no comment lines. ; DELIMITER - Character(s) specifying delimiter used to separate ; columns. Usually a single character but, e.g. delimiter=':,' ; specifies that either a colon or comma as a delimiter. ; The default delimiter is either a comma or a blank. ; /NAN - if set, then an empty field will be read into a floating or ; double numeric variable as NaN; by default an empty field is ; converted to 0.0. ; /PRESERVE_NULL - If set, then spaces are considered to be valid fields, ; useful if the columns contain missing data. Note that between ; April and December 2006, /PRESERVE_NULL was the default. ; SKIPLINE - Scalar specifying number of lines to skip at the top of file ; before reading. Default is to start at the first line. ; NUMLINE - Scalar specifying number of lines in the file to read. ; Default is to read the entire file ; ; OUTPUTS: ; V1,V2,V3,...V25 - IDL vectors to contain columns of data. ; Up to 25 columns may be read. The type of the output vectors ; are as specified by FORMAT. ; ; EXAMPLES: ; Each row in a file position.dat contains a star name and 6 columns ; of data giving an RA and Dec in sexigesimal format. Read into IDL ; variables. (NOTE: The star names must not include the delimiter ; as a part of the name, no spaces or commas as default.) ; ; IDL> FMT = 'A,I,I,F,I,I,F' ; IDL> READCOL,'position.dat',F=FMT,name,hr,min,sec,deg,dmin,dsec ; ; The HR,MIN,DEG, and DMIN variables will be integer vectors. ; ; Alternatively, all except the first column could be specified as ; floating point. ; ; IDL> READCOL,'position.dat',F='A',name,hr,min,sec,deg,dmin,dsec ; ; To read just the variables HR,MIN,SEC ; IDL> READCOL,'position.dat',F='X,I,I,F',HR,MIN,SEC ; ; RESTRICTIONS: ; This procedure is designed for generality and not for speed. ; If a large ASCII file is to be read repeatedly, it may be worth ; writing a specialized reader. ; ; Columns to be read as strings must not contain the delimiter character ; (i.e. commas or spaces by default). Either change the default ; delimiter with the DELIMITER keyword, or use READFMT to read such files. ; ; Numeric values are converted to specified format. For example, ; the value 0.13 read with an 'I' format will be converted to 0. ; ; PROCEDURES CALLED ; GETTOK(), STRNUMBER() ; The version of STRNUMBER() must be after August 2006. ; NOTES: ; Since V6.1, READCOL uses the SCOPE_VARFETCH function rather ; than EXECUTE(). This is faster and allows readcol.pro to be used ; in the IDL Virtual machine. ; REVISION HISTORY: ; Written W. Landsman November, 1988 ; Modified J. Bloch June, 1991 ; (Fixed problem with over allocation of logical units.) ; Added SKIPLINE and NUMLINE keywords W. Landsman March 92 ; Read a maximum of 25 cols. Joan Isensee, Hughes STX Corp., 15-SEP-93. ; Call NUMLINES() function W. Landsman Feb. 1996 ; Added DELIMITER keyword W. Landsman Nov. 1999 ; Fix indexing typos (i for k) that mysteriously appeared W. L. Mar. 2000 ; Hexadecimal support added. MRG, RITSS, 15 March 2000. ; Default is comma or space delimiters as advertised W.L. July 2001 ; Faster algorithm, use STRSPLIT if V5.3 or later W.L. May 2002 ; Accept null strings separated by delimiter ,e.g. ',,,' ; Use SCOPE_VARFETCH instead of EXECUTE() for >V6.1 W.L. Jun 2005 ; Added compile_opt idl2 W. L. July 2005 ; Added the NaN keyword W. L August 2006 ; Added /PRESERVE_NULL keyword W.L. January 2007 ; Assume since V5.6 (FILE_LINES available ) W.L. Nov 2007 ; Assume since V6.1 (SCOPE_VARFETCH available) W. L. Dec 2007 ;- On_error,2 ;Return to caller compile_opt idl2 if N_params() lt 2 then begin print,'Syntax - READCOL, name, v1, [ v2, v3,...v25, /NAN' print,' FORMAT= ,/SILENT ,SKIPLINE =, NUMLINE = , /DEBUG]' return endif ; Get number of lines in file nlines = FILE_LINES( name ) if nlines LE 0 then begin message,'ERROR - File ' + name+' contains no data',/CON return endif if keyword_set(DEBUG) then $ message,'File ' + name+' contains ' + strtrim(nlines,2) + ' lines',/INF if not keyword_set( SKIPLINE ) then skipline = 0 nlines = nlines - skipline if keyword_set( NUMLINE) then nlines = numline < nlines ncol = N_params() - 1 ;Number of columns of data expected vv = 'v' + strtrim( indgen(ncol)+1, 2) nskip = 0 if N_elements(fmt) GT 0 then begin ;FORMAT string supplied? if size(fmt,/tname) NE 'STRING' then $ message,'ERROR - Supplied FORMAT keyword must be a scalar string' ; Remove blanks from format string frmt = strupcase(strcompress(fmt,/REMOVE)) remchar, frmt, '(' ;Remove parenthesis from format remchar, frmt, ')' ; Determine number of columns to skip ('X' format) pos = strpos(frmt, 'X', 0) while pos NE -1 do begin pos = strpos( frmt, 'X', pos+1) nskip = nskip + 1 endwhile endif else begin ;Read everything as floating point frmt = 'F' if ncol GT 1 then for i = 1,ncol-1 do frmt = frmt + ',F' if not keyword_set( SILENT ) then message, $ 'Format keyword not supplied - All columns assumed floating point',/INF endelse nfmt = ncol + nskip idltype = intarr(nfmt) ; Create output arrays according to specified formats k = 0L ;Loop over output columns hex = bytarr(nfmt) for i = 0L, nfmt-1 do begin fmt1 = gettok( frmt, ',' ) if fmt1 EQ '' then fmt1 = 'F' ;Default is F format case strmid(fmt1,0,1) of 'A': idltype[i] = 7 'D': idltype[i] = 5 'F': idltype[i] = 4 'I': idltype[i] = 2 'B': idltype[i] = 1 'L': idltype[i] = 3 'Z': begin idltype[i] = 3 ;Hexadecimal hex[i] = 1b end 'X': idltype[i] = 0 ;IDL type of 0 ==> to skip column ELSE: message,'Illegal format ' + fmt1 + ' in field ' + strtrim(i,2) endcase ; Define output arrays if idltype[i] GT 0 then begin (SCOPE_VARFETCH(vv[k], LEVEL=0))= $ make_array(nlines,TYPE = idltype[i]) k = k+1 endif endfor goodcol = where(idltype) idltype = idltype[goodcol] check_numeric = (idltype NE 7) openr, lun, name, /get_lun ngood = 0L temp = ' ' skip_lun,lun,skipline, /lines if not keyword_set(delimiter) then delimiter = ' ,' for j = 0L, nlines-1 do begin readf, lun, temp if strlen(temp) LT ncol then begin ;Need at least 1 chr per output line ngood = ngood-1 if not keyword_set(SILENT) then $ message,'Skipping Line ' + strtrim(skipline+j+1,2),/INF goto, BADLINE endif k = 0 temp = strtrim(temp,1) ;Remove leading spaces if keyword_set(comment) then if strmid(temp,0,1) EQ comment then begin ngood = ngood-1 if keyword_set(DEBUG) then $ message,'Skipping Comment Line ' + strtrim(skipline+j+1,2),/INF goto, BADLINE endif var = strsplit(strcompress(temp),delimiter,/extract, preserve=preserve_null) if N_elements(var) LT nfmt then begin if not keyword_set(SILENT) then $ message,'Skipping Line ' + strtrim(skipline+j+1,2),/INF ngood = ngood-1 goto, BADLINE ;Enough columns? endif var = var[goodcol] for i = 0L,ncol-1 do begin if check_numeric[i] then begin ;Check for valid numeric data tst = strnumber(var[i],val,hex=hex[i],NAN=nan) ;Valid number? if tst EQ 0 then begin ;If not, skip this line if not keyword_set(SILENT) then $ message,'Skipping Line ' + strtrim(skipline+j+1,2),/INF ngood = ngood-1 goto, BADLINE endif (SCOPE_VARFETCH(vv[k], LEVEL=0))[ngood] = val endif else $ (SCOPE_VARFETCH(vv[k], LEVEL=0))[ngood] = var[i] k = k+1 endfor BADLINE: ngood = ngood+1 endfor free_lun,lun if ngood EQ 0 then begin message,'ERROR - No valid lines found for specified format',/INFORM return endif if not keyword_set(SILENT) then $ message,strtrim(ngood,2) + ' valid lines read', /INFORM ; Compress arrays to match actual number of valid lines for i=0,ncol-1 do $ (SCOPE_VARFETCH(vv[i], LEVEL=0)) = $ (SCOPE_VARFETCH(vv[i], LEVEL=0))[0:ngood-1] return end