How do I perform a mathematical operation on the data and the axis of a .*fig, such as re-scaling?

I have a figure with several functions plotted on it. I don't have the original data for all the function in arrays or matrices. I wish to perform some mathematical manipulations on the data and the axes, such as - x->x*x0, y->y/x0 (simple re-scaling), or other, more complicated ones such as x->x^2, y->y mod 2. This is more than just changing the labels on the axes. How do I do that? THX on advance!

Answer 1

[Ced]

For plotting, Matlab displays everything according to data points, i.e. it doesn't anything about the underlying function. It you want to change the underlying function, the only way I can think of (except changing the Ticks for simple scaling), is the following:

1. extract data

See How to extract data from a figure

2. perform operation

3. update, e.g. either create a new plot, or update the existing data as

xdata = set(dataObjs, 'XData');
ydata = set(dataObjs, 'YData');
zdata = set(dataObjs, 'ZData');

Cheers

[Star Strider]

Note that getting the data from a .fig file is different between versions before R2014b, and R2014b and since.

See Walter’s Comment for details on the procedure required in R2014b and after.