[SOLVED] open files with ascending numbers

vjramana · 04-30-2013, 08:21 PM

I am trying to generate files in fortran90 with ascending number in the filename. The fortran code I used is as blow:

Code:

program openfile
implicit none

integer::i, j
 character (len=90) :: filename


	fileLoop: do j = 31, 40

	 write (filename, '( "test-set",I2,".traj" )' ) (j-30)
	 OPEN(unit=j,status='unknown',file=filename)
	 close (j)

	end do fileLoop


end

I get the files with name as below:

Code:

test-set10.traj
test-set 1.traj
test-set 2.traj
test-set 3.traj
test-set 4.traj
test-set 5.traj
test-set 6.traj
test-set 7.traj
test-set 8.traj
test-set 9.traj

The problem I am finding here is the single digit number after the "set" word. The number is not like "set1", "set2" and I want to get until "set60". Instead there is an empty space if I use I2 in the code above. I want the file names to be:

Code:

test-set1.traj
test-set2.traj
test-set3.traj
test-set4.traj
test-set5.traj
test-set6.traj
test-set7.traj
test-set8.traj
test-set9.traj
test-set10.traj

Can anyone help me to fix this problem?

Many thanks in advance.

Regards

flos · 04-30-2013, 09:40 PM

Dear vjramana,
even if you achieve what you are aiming for, when viewed in a file explorer (eg Nautilus or Dolphin) or even under a command-line ls, they will not appear in the numerical order you expect: you will always get xx1, xx10, xx12, xx2, etc. If you expect a maximum of, say, a hundred files, the numerical string you want to append to xx should be padded with a single leading zero, so that you will get xx01, xx02, xx03 ... xx09, xx10, xx11 and so on.
If the expected number of files is up to a thousand, you would need to pad with two zeros, to get xx001, xx002, etc.
I don't recognise the language you are programming in, but usually there are provisions for doing this left-side padding with zeros for the counter (i or j) that you are using to iterate through the sequence of files.
The counter is an integer; to create a file name (which is a string), you have to convert the integer to a string, and usually the programming language allows you to format integers as strings of any chosen length (I presume that is what the I2 in your example is trying to do), but you may have to specify what the padding character is going to be. It seems from your results that your programming language has used a default of a space as padding character. Personally, I find that file names with spaces in them cause so many problems that I *never* use spaces in file names. You wouldn't find a single example in my entire workspace.
In the hope that this helps, may I wish you the best of luck?
Regards, Flos

psionl0 · 05-01-2013, 12:41 AM

It's been a while since I used fortran but you could try the following code:

Code:

write(str1,I3) (j-30)
adjustl(str1)
str2 = '000'//str1
n = len_trim(str2)
filename = "test-set"//str2(n-2,n)//".traj"

I'm guessing it should generate the following filenames:

Code:

test-set001.traj
test-set002.traj
test-set003.traj
test-set004.traj
test-set005.traj
test-set006.traj
test-set007.traj
test-set008.traj
test-set009.traj
test-set010.traj