[Pw_forum] inverse participation ratio

[Roberto Guerra]

Hello,

I wish calculate the inverse participation ratio (IPR) as post processing of 
pwscf.

this is the formula:
http://ulisse.fisica.unimo.it/ipr.png

where "i" is the index of the volume element.

The problem (beside my unaptness about fortran) is that the wave functions are 
in the real space, and therefore I guess I have to call an inverse fft for 
each IPR calculation.

What do you think is the best way to code such a thing? As a separate program 
or together with pp or some other tool? Is there any source where to take 
routines suitable for this task?

Thank you,
Roberto.