Change Y-Variable to Ln Y in Gnuplot: How-To Guide for Linear Graphing

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VenaCava
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Is there an easy way to change your y-variable in Gnuplot to ln y without changing the source data file?
I already tried "set log y" but that only changed the y-axis scale, not the actual y-values.
Right now I'm plotting an exponential decay and I wanted to make it a linear graph (lny vs time).

Thanks
 
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Hi VenaCava,

VenaCava said:
Is there an easy way to change your y-variable in Gnuplot to ln y without changing the source data file?
I already tried "set log y" but that only changed the y-axis scale, not the actual y-values.
Right now I'm plotting an exponential decay and I wanted to make it a linear graph (lny vs time).

Thanks

I'm not sure if this is what you want, but if you are using a data file "data.txt" with x and y columns, you can plot the natural log of the y columns with the command:

Code: 
plot 'data.txt' u 1:(log($2))