sp_validation

Validation of weak-lensing catalogues (galaxy and star shapes and other parameters) produced by ShapePipe.

Usage	Development	Release

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Authors: CosmoStat lab at CEA Paris-Saclay; Martin Kilbinger, Axel Guinot.
Contributors: Emma Ayçoberry, Lucie Baumont, Clara Bonini, Cail Daley, Samuel Farrens, Sacha Guerrini, Fabian Hervas Peters.
Email: [email protected]

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This package contains a library and several scripts and notebooks. The main tasks that can be performed by sp_validation are:

• Shear validation, in particular for the output of the shapepipe pipeline. This task takes on input a shear catalogue with metacal information, performs the calibration and carries out various tests, e.g. PSF leakage. A calibrated shear catalogue is then created on output.
• Post processing. A number of scripts allow further processing of the above output calibrated shear catalogue.
• Cosmology validation. This task uses the calibrated shear catalogue from above to run detailed diagnostics useful for further cosmology analysis, e.g. rho- and tau-statistics, E-/B-mode decomposition. Several catalogues can be compared and useful plots are created.
• Cosmology inference. This task uses the calibrated shear catalogue from a shear validation run and performes cosmology inference using the two-point correlation function.

Container Installation (Recommended)

The easiest way to install sp_validation is via a container. Docker images are automatically built and pushed to the Github Container Registry (GHCR) for each release. This image can be installed and run on most systems (including clusters) with just a few lines of code.

We recommend running the image with Apptainer (formerly Singularity) which is installed on most HPC clusters. To simply run the image, use the following command:

# build writeable "sandbox" container in the current directory
# ./sp_validation will be a directory that functions like a vm
apptainer build --sandbox sp_validation docker://ghcr.io/cosmostat/sp_validation:develop

# open a shell in the container
apptainer shell --writable sp_validation 
# and confirm that the installation was successful
python -c "import sp_validation"

You can also run the image with Docker:

docker run --rm -it ghcr.io/cosmostat/sp_validation:pyproject_docker python -c "import sp_validation"  

We do not currently build images for Apple Silicon/amr64; however the amd64 images should work on these systems, albeit with reduced performance.

Flow chart

The following flow chart illustrates the steps required to go from ShapePipe output products to calibrated and well-selected galaxy catalogues.

Run shear validation

See the documentation for instructions on how to set up and run sp_validation.

Post processing

The output(s) of one or more shear validation runs can be processed further with post-processing scripts. See here for details.

Cosmology validation

TBD.

Cosmology inference

See the corresponding documentation.