Avoid unnecessary download of large Psi4 data in RIT + standardize variable names across catalogs

[koustavchandra]

Summary

Currently, the RIT handler in PyART downloads the full ExtrapPsi4 directory even when psi_load=False is specified. This leads to unnecessarily large downloads, especially when users only intend to access strain data or metadata.

Additionally, the variables provided by the RIT catalog differ slightly from the SXS variables. Since a key goal of PyART is to provide a unified interface across waveform catalogs, it would be beneficial to enforce consistency in naming.

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✅ Proposed Solution

1. Conditional Psi4 Download

• Modify the download_data() method in the RIT.
• If psi_load=False, skip downloading Psi4 files entirely.
• If psi_load=True:
  • Check whether ExtrapPsi4* data already exists locally.
  • If it does not exist, download it.
  • If it does exist, skip the download.

This ensures that Psi4 data is only fetched on demand, saving bandwidth and storage.

[RoxGamba]

Agreed this is something to be fixed. In general, we should try to unify the various inputs for the Waveform_* classes. For instance, SXS waveforms take a download, a downloads and a load argument to decide whether to download anything and -- in case -- what to download/load. Something similar could be done for RIT, CoRe etc.