A Save Time with CLASS Code: Neat Trick for Background Quantity Evolution

AI Thread Summary
The discussion focuses on optimizing the CLASS code by bypassing the internal Boltzmann solver to save time when calculating background quantities. Users seek methods to directly compute background evolution without evaluating perturbations or transfer functions. The main goal is to streamline the process for those only interested in background dynamics. Suggestions include modifying the code or using specific settings to achieve this efficiency. Overall, the thread emphasizes the need for faster computations in cosmological simulations.
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Is there a neat way to "not" run the internal Boltzmann solver (for perturbations) in CLASS code and rather just solve for the background quantities? This way I can save the time otherwise spent in evaluating the perturbations and transfer functions. I am only interested in the time evolution of background quantities.
 

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