如何在 xmgrace 中添加顶部 x 轴？

Question

I have plotted a graph with xmgrace, the x-values are in linear scale of nm (for wavelength). I want to add a top reciprocal x-axis in eV units.

The formula to transform nm to eV is:

I could not find a way to add another x-axis without adding a new data set.

Answer 1

This is possible without any particular hack which, since we are dealing with xmgrace, is quite amazing:-) Here is how you do it:

• Open the axis properties
• Select the "Alt X axis" option in the "edit" drop-down menu
• Go to the "Tick labels" tab
• Select "Opposite" as the Placement side
• Put "1240 / $t" in the "Axis transform" textbox at the bottom
• Click "Apply"