Question

I want to show how used space changes on my disk by drawing a figure with x-axis the sampling time point and y-axis storage used on disk.
However, currently, the storage used is recorded in bytes, which is not human-readable when value goes beyond GB.

So, could I re-tic axis in gnuplot? In my case, could I change the value 100000000, for example, into 100MB?

Thanks and Best Regards.

Answer 1

You have two main options. The first (and probably easiest) is to scale things when you plot:

plot 'datafile' using 1:($2/1e6) title 'Usage in MB'

This will plot the second data column in the file datafile with each value divided by 1e6, versus time (first column).

You can also re-tic the axes, but this is a bit less general.

set ytics ("100" 1e8)

Another option would be to use scientific notation on the y axis (as I have been doing with these big numbers above). To do that, the command is

set format y '%.2e'

This will print the y tics using scientific notation with 2 figures after the decimal point. You could also try

set format y '%.2g'

which will print the more compact of either scientific or normal notation.