The basis of EPC matrix element g

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Dear all,

As we know, the electron-phonon coupling matrix g can emerge on the orbital basis and band basis. I was wondering which basis is used in the EPW output. Based on my understanding, the g used in the EPW is on the band basis, which should have an arbitrary phase factor. However, the EPW output is |g| and ignores the phase factor. So why the EPW outputs |g| instead of g?
Thank you.

Best regards,
Zishen