Add fourth column into an original file

[Khaled Tahoon]

I have an original ASCII data file with 3 columns and 1000 raw.  I wrote IDL code to calculate a new parameter with one column and 1000 raw. I would like to modify my own code to merge directly the new parameter  into original file to becomes 4 columns and 1000 raw.

thanks in advance

Khaled

[Nikola Vitas]

The solution may depend on the exact content of the ascii file, but something like this should give you the idea.

filename_old = 'old.dat'

filename_old = 'new.dat'

ncol = 3

nrow = 1000

old = DBLARR(ncol, nrow)

new = DBLARR(ncol+1, nrow)

OPENR, 1, filename_old

READF, 1, old

CLOSE, 1

new[0:ncol-1, *] = old

new[ncol, *] = ... ; new values

OPENW, 1, filename_new

PRINTF, 1, new

CLOSE, 1

[Khaled Tahoon]

thank you for help

Just I have 132 files, each one contains  9 columns and 1000 raw. what I need, I select I last column from all files and print them in one file name out.txt

the outcome file becomes a matrix of 132 columns and 1000 raw. for this idea I wrote the following code

input_dir_model = 'C:\Users\Desktop\Input_data'                                                         ; This directory contains 132 files
fileList_model = FILE_SEARCH(input_dir_model,'*', /FULLY_QUALIFY_PATH )   ; select all files in the input directory

output_dir_pw = 'C:\Users\Desktop\out_parameter'

FOR i = 0, n_elements(file_list_model) -1  DO BEGIN

date=file_lines( file_list_model (i))  ;     the number of lines in each file
t_data=fltarr(9,date)                      ;     the number of columns in each files
openr, lun,  fileList_model (i),/get_lun  
readf, lun, t_data
free_lun, lun
X1  =reform(t_data[0,*])    ; the first column
X2   =reform(t_data[1,*])   ; the second column
X3   =reform(t_data[2,*])
X4    =reform(t_data[3,*])
X5    =reform(t_data[4,*])
X6    =reform(t_data[5,*])
X7   =reform(t_data[6,*])
X8    =reform(t_data[7,*])
X9    =reform(t_data[8,*])    ; the last column



OPENW, lun, ' output_dir_pw \temp.txt\out.txt', /get_lun; , /append
PRINTF, lun, [X9[0:i,*]], format='(3x, f8.4)'     
free_lun,lun

end

it's suppose that the code print X9's  columns in out.txt.

Unfortunately, The code don't  run correctly

Best regards