### Boltzmann codes: CAMB, CLASS compute two-point angular corre

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**May 04 2015**I am struggling to use CAMB or CLASS to directly compute and plot the two-point temperature correlation function C(theta). (See for example first-year WMAP release, astro-ph/0302207v3, equations (5) and (6) in Section 7. Full derivation found in Durrer 2008 textbook "The Cosmic Microwave Background", equation 2.240.) The measured quantity was released as a WMAP first-year data product. I would like to plot the theoretical prediction C(theta) versus theta.

Naturally, I can manipulate the CAMB- or CLASS-generated outputs C_l and ell in order to calculate this expression. I could then convert ell values into theta, and plot the results. However, I would ideally like to directly compute C(theta) using Boltzmann codes. Is there a method to do this?

Naturally, I can manipulate the CAMB- or CLASS-generated outputs C_l and ell in order to calculate this expression. I could then convert ell values into theta, and plot the results. However, I would ideally like to directly compute C(theta) using Boltzmann codes. Is there a method to do this?