Spectrum display; export to CSV etc.

The spectrum display can be moved using the mouse right-click-hold and drag. By setting the cursor over one of the axes, they can be zoomed in and out (scale changed) using the scroll wheel or by mouse left-click-hold and drag.

This is all standard PyQtGraph functionality.

Clicking on the small 'A' that appears in the bottom left corner when the mouse cursor is over the graph will set the graph to auto-scale. It can be returned to fixed scale using the scroll wheel.

Right-click on the graph brings up a menu where there are many options, for example in 'plot options' the X and Y grid can be turned on/off and its opacity can be changed.

The 'export' option allows the graph data to be exported as CSV or various image files, or as a Matplotlib window.