conjugate of tail of ImFreq Greens functions

[aichhorn]

there is a problem with the conjugate of the tail of a Greens function. Because of the expansion in 1/iomega, one has to conjugate to whole tail, not only its coefficients. bug is in tail.pyx maybe put a special function for ImFreq GF's, since it is not needed anywhere else.

[parcollet]

To be rechecked in branch 1.2-dev.

[parcollet]

@pseth, @aichhorn: can you recheck ? Is it fixed in 1.2-dev ?

[krivenko]

@parcollet No, it is not fixed.

from pytriqs.gf.local import *

g = GfImFreq(indices = [0], beta = 1)
g <<= inverse(Omega)

print g.tail[1]                 # [[ 1.-0.j]]
print g.conjugate().tail[1]     # [[ 1.+0.j]]

[parcollet]

Retested. IT works now. Closed.

[mferrero]

It's not fixed... The tail of the conjugate of a Green's function is not the conjugate of the tail. The conjugate has to be specialized for the different kinds of GFs...

[pseth]

We need to fix this asap.

[parcollet]

Ah, ok. @mferrero : Can you be more precise what you mean by specialized ?

[mferrero]

Take 1/i\omega_n. Its first moment is 1. The complex conjugate is -1/i\omega_n with first moment -1. Clearly the tail of the conjugate is not the conjugate of the tail. It has an extra -1 factor. On the other hand, take the function 1/\omega. The complex conjugate is 1/\omega. Both first moments are 1. In that case, no need to take an extra -1 factor. So according to the type of the Green's function, the procedure to get the tail of the conjugate is different. We will have to code a specialized version of conjugate for all Green's functions no?

[parcollet]

Ah right ... Needs to be done soon, Leonid needs it...

[tayral]

+1