add distillation of diag file statistics to ocnanalvrfy task

[AndrewEichmann-NOAA]

This adds to the ocnanalvrfy a step that untars and unzips collected diag files from cnvstats and performs some basic averaging on the t and sst variables, with the goal of providing quick statistics from them without the need for post-experiment processing.

Todo issues include removal of the tar and gunzip commands to the jjob (put here to get something working relatively quick), and some refinement of the t filters to get over-ocean observations.

File added:
ush/diag_statistics.py
File changed:
scripts/exgdas_global_marine_analysis_vrfy.py

Addresses #479

[CoryMartin-NOAA]

Couple of comments, things look fine, my approval depends on how 'permanent' this script is.

[AndrewEichmann-NOAA]

@CoryMartin-NOAA Could you elaborate on the point about permanence?

[emcbot]

Automated Global-Workflow GDASApp Testing Results:
Machine: hera

Start: Wed May 24 16:05:34 UTC 2023 on hfe07
---------------------------------------------------
Build:                                 *SUCCESS*
Build: Completed at Wed May 24 17:09:25 UTC 2023
---------------------------------------------------
Tests:                                 *SUCCESS*
Tests: Completed at Wed May 24 17:21:57 UTC 2023
Tests: 100% tests passed, 0 tests failed out of 49

[CoryMartin-NOAA]

@AndrewEichmann-NOAA if this is intended to be used for weeks/months+, then go with import tarfile, if this is just a quick and dirty thing that will go away soon, this is fine.

[CoryMartin-NOAA]

one comment, otherwise looks good

[guillaumevernieres]

👍