Version 6 (modified by smueller, 13 months ago) (diff)

ENHANCE-05_SimonM-Harmonic_Analysis

Last edition: 12/09/19 19:18:03 by smueller

The PI is responsible to closely follow the progress of the action, and especially to contact NEMO project manager if the delay on preview (or review) are longer than the 2 weeks expected.

  1. Summary
  2. Preview
  3. Tests
  4. Review

Summary

The harmonic-analysis diagnostics available in the current reference code is limited to two-dimensional fields (surface only), is activated via a preprocessor key, uses unconventional namelist parameter names, uses a mixture of dynamic and static allocation for large arrays, and appears to be computationally inefficient. Further, while being based on multiple linear regression, the current implementation does not provide for regressions on harmonic components other than tidal constituents.

This action will replace the current tidal harmonic-analysis diagnostics with a generic implementation for multiple linear regression analysis that can be utilised for both tidal harmonic and non-tidal regression analyses. This implementation will provide harmonic-analysis diagnostics enhancements previously tested in a pre-4.0beta NEMO version by N. Bruneau: the analysis of three-dimensional fields, analysis across model restarts, and improved computational efficiency.

In contrast to both the existing harmonic analysis diagnostics in the reference NEMO code and the enhanced pre-4.0beta version by N. Bruneau, the new implementation will make extensive use of XIOS and an off-line tool. This approach should make it possible to simplify the regression analysis-related Fortran module in the core NEMO code, to relocate the regression-analysis configuration to XIOS configuration files, and to enable the selection of any model field handled by XIOS for analysis.

See ticket #2175.

Preview

Since the preview step must be completed before the PI starts the coding, the previewer(s) answers are expected to be completed within the two weeks after the PI has sent the request to the previewer(s).
Then an iterative process should take place between PI and previewer(s) in order to find a consensus

Possible bottlenecks:

  • the methodology
  • the flowchart and list of routines to be changed
  • the new list of variables wrt coding rules
  • the summary of updates in literature

Once an agreement has been reached, preview is ended and the PI can start the development into his branch.

Tests

Once the development is done, the PI should complete the tests section below and after ask the reviewers to start their review.

This part should contain the detailed results of SETTE tests (restartability and reproducibility for each of the reference configuration) and detailed results of restartability and reproducibility when the option is activated on specified configurations used for this test

Regular checks:

  • Can this change be shown to produce expected impact (option activated)?
  • Can this change be shown to have a null impact (option not activated)?
  • Results of the required bit comparability tests been run: are there no differences when activating the development?
  • If some differences appear, is reason for the change valid/understood?
  • If some differences appear, is the impact as expected on model configurations?
  • Is this change expected to preserve all diagnostics?
  • If no, is reason for the change valid/understood?
  • Are there significant changes in run time/memory?

Review

A successful review is needed to schedule the merge of this development into the future NEMO release during next Merge Party (usually in November).

Assessments:

  • Is the proposed methodology now implemented?
  • Are the code changes in agreement with the flowchart defined at preview step?
  • Are the code changes in agreement with list of routines and variables as proposed at preview step?
    If, not, are the discrepancies acceptable?
  • Is the in-line documentation accurate and sufficient?
  • Do the code changes comply with NEMO coding standards?
  • Is the development documented with sufficient details for others to understand the impact of the change?
  • Is the project literature (manual, guide, web, …) now updated or completed following the proposed summary in preview section?

Finding:

Is the review fully successful? If not, please indicate what is still missing


Once review is successful, the development must be scheduled for merge during next Merge Party Meeting.