Re: Writing to ASCII files

[Craig Markwardt <craigmnet(at)cow.physics.wisc.edu>]

Jasmeet Judge <jjudge@indiana.edu> writes:

> 1. When I use printf (and even writeu), it gives me
> non-sensible results. Here is what I am doing
> 
> openw,unitno,filename
> some loop with i
> printf,unitno,item1(i),item2(i)
> end loop
> close,unitno
> 
> What I would like is:
> item1(0) item2(0)
> item1(1) item2(1)
> item1(2) item2(2)
> item1(3) item2(3)

Hi Jasmeet, what you have here looks like the right invocations, so I
am a little confused why you get garbage out.  You can use a FORMAT
keyword as the other poster suggested, but by default you should get
something reasonable.  Can you post the actual code (+ snippet of
data)?  The only way I know to get unformatted/binary data out is to
use the WRITEU procedure.

> 2. Is there a way to open a file to write (with openw) but have
> it keep appending data at the end of file with every call to printf?
> 
> It would simplify my life considerably, if I can figure this
> out! I have avoided dealing with this for too long....

The documentation is your friend.  How about,

openu, unit, filename, /append
printf, unit, snorgle
close, unit

OPENU is for "update", and APPEND ensures that the file pointer is at
the end of the file.

Good luck,
Craig

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Craig B. Markwardt, Ph.D.         EMAIL:    craigmnet@cow.physics.wisc.edu
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