file_size.pro

;+
; NAME:
; FILE_SIZE
;
; PURPOSE:
; This function finds the number of bytes in an ASCII data file.
; It should be platform independent (well Windows and UNIX at least!).
;
; CATEGORY:
; Read/Write OR Input/Output.
;
; CALLING SEQUENCE:
;
; Result = FILE_SIZE(File_name)
;
; INPUTS:
; File_name: The name of the file to find the number of bytes in.
;
; OUTPUTS:
; This function returns the number of bytes in a file.
;
; PROCEDURE:
; Uses fstat to find information about the opened unit number.
;
; EXAMPLE:
; To find the size in bytes of the file test.dat enter:
; IDL> out=FILE_SIZE('test.dat')
;
; MODIFICATION HISTORY:
; Copyright    R.Bauer 2. Jan. 1996
; The idea to use fstat instead of spawn ls -l was given by Phil Williams.
;
; Modified by Paul Krummel, 12 February 1997, CSIRO Division of Atmospheric
; Research. Changed error messages to english and modified them. Added complete
; header information and usage information (help keyword).
; Added some more comments and a check to see if filename is a string.
;-

FUNCTION FILE_SIZE, filename, help=help
;print,'here',filename
;
; =====>> HELP
;
on_error,2
if (N_PARAMS(0) lt 1) or keyword_set(help) then begin
   doc_library,'FILE_SIZE'
   if N_PARAMS(0) ne 1 and not keyword_set(help) then $
               message,'Incorrect number of parameters, see above for usage.'
   return,-1
;
   ioerr:
   message,'Error reading file, '+filename+', does not exist' ,/inform
   return,-1
   filerr:
   message,'Filename must be of type string' ,/inform
   return,-1
endif
;
; ++++
; Check the filename to see if it is a string, if not display error message.
if type(filename) ne 7L then goto, filerr
;
; ++++
; Open the file name, if it does not exist, display error message.
openr, lun, filename, /get_lun, error=err
if err ne 0 then goto, ioerr
;
; ++++
; Use the fstat function to find information about the opened unit.
stats = fstat(lun)
free_lun, lun
;
; ++++
; Return the file size!
return, stats.size
;
; ++++
end

;+
; NAME:
; TYPE
;
; PURPOSE:
; Finds the type class of a variable.
;
; CATEGORY:
; Programming.
;
; CALLING SEQUENCE:
; Result = TYPE(X)
;
; INPUTS:
;    X
; Arbitrary, doesn't even need to be defined.
;
; OUTPUTS:
; Returns the type of X as a long integer, in the (0,11) range.
;  0 Undefined
;  1 Byte
;  2 Integer
;  3 Long integer
;  4 Float
;  5 Double precision
;  6 Complex number
;  7 String
;  8 Structure
;  9   Double complex
;  10 Pointer
;  11 Object reference
;
; PROCEDURE:
; Extracts information from the SIZE function.
;
; EXAMPLE:
; To find the type class of a variable:
; IDL> print,TYPE(7)
;   2
; IDL> print,TYPE(7D)
;   5
; IDL> print,TYPE('7')
;   7
;
; MODIFICATION HISTORY:
; Created 15-JUL-1991 by Mati Meron, University of Chicago.
; Modified 7 November 1997 by Paul Krummel,
; CSIRO Division of Atmospheric Research.
; Added in help message and expanded header
; info (Pointers and Object references).
;
;-
Function Type, x, help=help
;
on_error,2
if keyword_set(help) then begin
   doc_library,'TYPE'
endif
;
; ++++
    dum = size(x)
    return, dum(dum(0) + 1)
;
; ++++
;
end

;+
; NAME:
; FILE_LINE
;
; PURPOSE:
; This function finds the number of lines in an ASCII data file.
; It should be platform independent (well Windows and UNIX at least!).
;
; CATEGORY:
; Read/Write OR Input/Output.
;
; CALLING SEQUENCE:
;
; Result = FILE_LINE(File_name)
;
; INPUTS:
; File_name: The name of the file to find the number of lines in.
;    This can now be an array of filenames!!
;
; OUTPUTS:
; This function returns the number of lines in a file. If the input is
; an array of filenames then the output is a long array with length of
; the input array plus 1. This array will contain the number of lines
; in each of the files plus the total number of lines for all the files
; combined.
;
; PROCEDURE:
; Calls FILE_SIZE.
;
; EXAMPLE:
; To find the number of lines in the file test.dat enter:
; IDL> out=FILE_LINE('test.dat')
;   OR
; IDL> files=['test1.dat','test2.dat','test3.dat']
; IDL> print,FILE_LINE(files)
;  15 20 30 65
;
; MODIFICATION HISTORY:
; Copyright    R.Bauer 2. Jan. 1996
;
; Modified by Paul Krummel, 12 February 1997, CSIRO Division of Atmospheric
; Research. Changed error messages to english and modified them. Added complete
; header information and usage information (help keyword).
; Added some more comments and a check to see if filename is a string.
;
; Modified by Paul Krummel, 8 January 1998. Has been considrably modified
; and can now take in an array of filenames or just one file name.
;-

FUNCTION FILE_LINE, filename, help=help
;
; =====>> HELP
;
on_error,2
if (N_PARAMS(0) lt 1) or keyword_set(help) then begin
   doc_library,'FILE_LINE'
   if N_PARAMS(0) ne 1 and not keyword_set(help) then $
      message,'Incorrect number of parameters, see above for usage.'
   return,-1
;
   ioerr:
   message,'Error reading file, '+filename+', does not exist' ,/inform
   return,-1
   filerr:
   message,'Filename(s) must be of type string' ,/inform
   return,-1
endif
;
; ++++
; Check the filename to see if it is a string, if not display error message.
if type(filename) ne 7L then goto, filerr
;
; ++++
; Find if the number of elements in the input (filename)
num=n_elements(filename)
;
; ++++
; If the input "filename" is an array loop around each file else just
; process as single filename.
CASE 1 of
;
; ****** Just a string ******
 num eq 1: BEGIN
; ++++
; Use the filesize function to find the number of bytes in the file. If
; there are no bytes then the file does not exist, print error message.
  byt=file_size(filename)
  if byt eq -1 then goto, ioerr
;
; ++++
; Set up byte array to length of the file.
  bytes=bytarr(byt)
;
; ++++
; Open the file name, if it does not exist, display error message.
  openr,lun,filename,/get_lun,error=err
  if err ne 0 then goto, ioerr
;
; ++++
; Read the file into the byte array.
  readu,lun,bytes
  free_lun,lun
;
; ++++
; Find where we have a line feeds and count them.
  line=where(bytes eq 10B,count_line)
;
; ++++
   END
;
; ++++
; ****** An array of strings ******
 num gt 1: BEGIN
; ++++
; Set up the ouput array, one extra that will contain the total of
; all the files.
  count_line=lonarr(num+1)
;
; Loop around the filenames
  For i=0,num-1 do begin
;
; ++++
; Use the filesize function to find the number of bytes in the file. If
; there are no bytes then the file does not exist, print error message.
   byt=file_size(filename[i])
   if byt eq -1 then goto, ioerr
;
; ++++
; Set up byte array to length of the file.
   bytes=bytarr(byt)
;
; ++++
; Open the file name, if it does not exist, display error message.
   openr,lun,filename[i],/get_lun,error=err
   if err ne 0 then goto, ioerr
;
; ++++
; Read the file into the byte array.
   readu,lun,bytes
   free_lun,lun
;
; ++++
; Find where we have a line feeds and count them.
   line=where(bytes eq 10B,cnt_line)
   count_line[i]=cnt_line
; ++++
  endfor
;
; ++++
; Now total all the file lines
  count_line[num]=total(count_line[0:num-1])
;
; ++++
   END
;
ENDCASE
;
; ++++
; Return the number of lines in the file.
return,count_line
;
; ++++
END