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LSSTDESC / N5K

Non-local No-Nonsense Non-Limber Numerical Knockout
BSD 3-Clause "New" or "Revised" License
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3C integration method #13

Closed jecampagne closed 2 years ago

jecampagne commented 3 years ago

Hello, Well I have not yet made progress

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Here is a set of formula (E1) is the formula in the Readme of N5K repo (E2 &E3) are a reformulation based on the hypothesis of factorization where one can identify the $f_\ell$ auxiliary function Now, (E4) is the approximation of the problem based on the sampling in z1/chi1 (z2/ch2) with for instance a 2D-trapezoidal quadrature which fixes the w_i and w_j weights the k-sampling and the use of my 3C integration package which can be used to integrate other sub-k-intervalles.

The 3cint.py is a Python version of the 3cint.cc C++ code, based on a C++ wrapping with SWIG of some C++-header code. As I am not an expert on C++->Python wrapping I can only tell that it works with Linux version and on some Mac-clang install (but not mine :( )

Well , now the tricky thing is to identify the f_ell(k,zi) et f_ell(k,zj) which are the connection with CLL based on Kernel functions & the spherical-bessel-functions.

The 3C algo is the heart of AngpowC++code but the framework (not only C++ vs Python) is completely different.

If someone can help, he/she is the welcome.

c-d-leonard commented 2 years ago

@jecampagne I am going to close this PR :)