[Tutor] Printing columns of data

[Kent Johnson]

Kooser, Ara S wrote:
> Hello all,
> 
>    I am writing a program to take a data file, divide it up into columns 
> and print the information back with headers. The data files looks like this
> 
>       0.0 -3093.44908 -3084.59762   387.64329    26.38518  0.3902434E+00 
> -0.6024320E-04  0.4529416E-05
>       1.0 -3094.09209 -3084.52987   391.42288   105.55994  0.3889897E+00 
> -0.2290866E-03  0.4187074E-03
>       2.0 -3094.59358 -3084.88826   373.64911   173.44885  0.3862430E+00 
> -0.4953443E-03  0.2383621E-02
>         etc…
>         10.0 ...
> 
> So I wrote the program included below and it only prints the last line 
> of the file.
> 
> Timestep    PE
> 10.0      -3091.80609
> 
> I have one question. Do I need to put ts and pe into a list before I 
> print then to screen or I am just missing something. Thanks.

You should print the header before the loop, and the contents inside the loop. So:
print """

Timestep    PE"""
for line in cols:
     ts = line[0]
#    print line[0]
     pe = line[1]
#    print line[1]

     # The next line is indented so it is included in the loop:
     print "%s      %s     " % (ts,pe)

You probably will want to set the field width in the print format so the columns all line up, 
something like this (just guessing on the widths):
     print "%10s %10" % (ts,pe)

You might be interested in this recipe which does a very slick job of pretty-printing a table:
http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/267662

Kent

> 
> Ara
> 
> import string
> 
> inp = open("fort.44","r")
> all_file = inp.readlines()
> inp.close()
> 
> outp = open("out.txt","w")
> 
> cols = map(string.split,all_file)
> ##print cols
> 
> Data = {}
> for line in cols:
>     ts = line[0]
> #    print line[0]
>     pe = line[1]
> #    print line[1]
> 
> print """
> 
> Timestep    PE"""
> print "%s      %s     " % (ts,pe)
> 
> 
> outp.close()
> 
> 
> ------------------------------------------------------------------------
> 
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