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Re: Variable for data column number?

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Subject	Re: Variable for data column number?
From	andreas.buchgraitz@gmail.com
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tirsdag den 29. april 2008 kl. 13.33.31 UTC+2 skrev Juergen Wieferink:
> Ingo Thies wrote:
> > c1=1;c2=2
> > plot 'file' using c1:c2
> > 
> > But is it also possible to use variables for column numbers as a
> > function argument? "$c1" or similar don't work. For now, I can only do
> > this by replacing the column specifier in all the lines by
> > search&replace, but a global switch would be much more convenient.
> 
> This could be done using macros "help macro", but the clean way is
> via the column() function (help column) [untested]:
> 
> c1=1;c2=2
> plot 'file' using (column(c1)):(column(c2))
> 
> 
> Juergen

Thanks, This works amazing if one wants to do math on each entry in a column, but directly in a bash script, for example subtracting some number from every entry: 

#!/bin/bash

gnuplot <<-EOF

set terminal pdf
set output "test.pdf"
plot "data.dat" u 1:(column(2)-2.63E-02) with lines

EOF

evince test.pdf

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Re: Variable for data column number? andreas.buchgraitz@gmail.com - 2020-01-30 08:53 -0800

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