Emulation and Assessment of Gradient-Based samplers in Cosmology

We integrate an emulator of the linear matter power spectrum in JAX-COSMO and we test the performance of difference samplers:

1. Cobaya
2. NUTS

Reference Papers

• arXiv:2302.05163
• arXiv:2105.12108
• arXiv:2310.08306

Running the Samplers

• For running NUTS:

python sample.py --config=config.py:desyr1 --config.sampler=nuts --config.nuts.nwarmup=100 --config.nuts.nsamples=15000 --config.nuts.nchain=2 --config.nuts.chainmethod=vectorized --config.use_emu=False --config.samplername=1

• For running Cobaya:

python samplecobaya.py

but we have to specify the setup (for example, number of samples) in the script first.

• For the Multivariate Normal Distribution and the Rosenbrock function, the notebooks rosenbrock.ipynb and multivariate.ipynb are used.