regexp: matching expressions b4 and after ....

[giovanni . lombardo]

Hi,

I'm trying to convert a set of matlab codes into Octave. These codes heavily 
use string manipulation functions

In particular I'm trying to extract a set of equations from an ASCII file. From 
these equations I extract/replace variables etc.

So, for example, I have g="x^(-1)+y(-1)+z(-1)=0"

I need to extract/replace x, y and (-1). So, for example, I used the command 
regexprep(g,'(?<=[a-z]*)\(\-[1-9]*\)','\_minus1')

which returned "x^(-1)+y_minus1+z_minus1"

Can I do the same in Octave? How?

Thansk,

Gianni