# Is it possible to multiply the x coordinates of a plot by a certain factor using pgfplots

I have a pgf plot. Now the scale on the x-axis is at the moment frequency, hz, but it should be rad/s to save myself time exporting the file again is it possible to multiply the x-coordinate of every data point with a certain factor easily in pgf plots? In this case 2*pi?

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use x expr as in

\addplot table[x expr=\thisrowno{0}*2*pi, y index=1] {\table};


assuming that your abscissas are stored in the first column of a table loaded in the macro \table and your ordinates in the second.

More details are given on page 29 of the pgfplots manual.

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How'd you do that with coordinates ? \addplot [...] coordinates { (0, 1) (1, 4) (2, 14) }; ? – hillbilly Apr 13 '15 at 12:46

Yes it is! From the pgfplots manual:

\documentclass{standalone}
\usepackage{pgfplots}
\begin{document}
\begin{tikzpicture}
\begin{axis}[
xtick={0,1.5708,...,10},
domain=0:2*pi,
scaled x ticks={real:3.1415},
xtick scale label code/.code={$\cdot \pi$}]

The option of interest is the scaled x ticks={real:3.1415}, which tells pgfplots to scale the x values by a factor of 3.1415. You can switch off the "times PI" part below the axis by removing the xtick scale label code/.code={$\cdot \pi$} code.
As far as I can see, the real:<num> scales the axis by dividing all the axis points by <num>´´. So if you want to end up with {2\pi}^2, you would have to scale the axis with 1/(2\pi)... – Benedikt Bauer Oct 6 '12 at 14:45