[Wien] 3D Frourier transform of the step functions

[fatemeh.mirjani]

Dear Prof. Blaha;

Would you please guide me that can I find  a subroutine for 3D Frourier transform of the step functions in the source of Wien2k?
If yes, Where?
 
I'm anxiously looking forward your reply.
With my best regards,
Fatemeh

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|Fatemeh Mirjani                              | Email: f_mirjani at ph.iut.ac.ir  |
|Computational Condensed Matter Research Lab. | Tel/Fax Office: +98311-3913746 |
|ICTP Affiliated Center in Isfahan,           | Tel Lab.: +98311-3913731       |
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