Change x-values in gnuplot

Question

I'm plotting a column of data which represents a time series in gnuplot. Every value represents a time value after 500 iterations / time units. Can I tell gnuplot to multiply the x-values it displays by 500?

I thought this would be a standard problem since every time one has to plot a time series one needs to tell the plotting program what time unit each iteration has.

I don't want to create an extra column with x-values manually, since I have a lot of different data of different length. I don't want to create a x column for everyone of them.

Answer 1

If you have only a single column, gnuplot uses the row number as x value. This can be accessed by the pseudo column 0 and scaled like

plot 'datafile' using ($0*500):1

or equivalently, if you're calling this from a shell script

plot 'datafile' using (column(0)*500):1