Use "column header" (text) as title?

[Joerg Hau]

Hi,

How can I retrieve a textual "column header" from a data file, to be
used as title or legend for a graphic?

Let's say file 'data' looks somewhat like this:

# Some text here here
min CmpA CmpB
30 12.5 19.0
40 15.5 15.2
50 17.1 12.2
60 20.0 10.9
70 21.1 9.0

... now I would like to "plot 'data' using 1:2 title $hdr_A, '' using
1:3 title $hdr_B" ... where $hdr_A and $hdr_B should ideally become
"CmpA" and "CmpB", yet automagically retrieved from the 2nd line of
the file.

I need to process a number of files like that, just with many more
columns and with plots involving different files ... hence the need
to be sure that I have the correct dataset on display.

Any ideas (or a suitable shell script ;-) for this purpose?

Cheers & thanks in advance,

- Joerg


--
joerg dot hau at swissonline dot ch * Lausanne, Switzerland
http://homepage.sunrise.ch/mysunrise/joerg.hau/
"All standard disclaimers apply".
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(this became necessary due to increasing SPAM)

[Ethan Merritt]

In article <0ndd1c...@54693.user.dfncis.de>,

Joerg Hau <nospam.j...@swissonline.ch> wrote:
>
>How can I retrieve a textual "column header" from a data file, to be
>used as title or legend for a graphic?
>
>Let's say file 'data' looks somewhat like this:
>
># Some text here here
>min CmpA CmpB
>30 12.5 19.0
>40 15.5 15.2
>50 17.1 12.2
>60 20.0 10.9
>70 21.1 9.0
>
>... now I would like to "plot 'data' using 1:2 title $hdr_A, '' using
>1:3 title $hdr_B" ... where $hdr_A and $hdr_B should ideally become
>"CmpA" and "CmpB", yet automagically retrieved from the 2nd line of
>the file.

If you are willing to build the development version from source, with
a patch applied, then you can get this behaviour easily. See the
sample output and explanation on my web site:
http://www.bmsc.washington.edu/people/merritt/gnuplot/

Using this patched version of gnuplot, the command you would use is

set key autotitle columnhead
plot 'data' using 1:2, '' using 1:3, ...

--
Ethan A Merritt

[Joerg Hau]

Hi Ethan,

>>How can I retrieve a textual "column header" from a data file, to be
>>used as title or legend for a graphic?
>

> If you are willing to build the development version

No problem with that :-)

> from source, with a patch applied, then you can get this behaviour
> easily. See the sample output and explanation on my web site:
> http://www.bmsc.washington.edu/people/merritt/gnuplot/
>
> Using this patched version of gnuplot, the command you would use is
>
> set key autotitle columnhead
> plot 'data' using 1:2, '' using 1:3, ...

Aaah ... yes, this works fine with your 'datastrings_3.8j.patch' and
3.8j (which is on my production machine). None of the two patches
worked cleanly with 3.8k1, though ... but I feel that's merely a
matter of some weeks ;-)

Thanks a lot,