Fix bugs in run_pcm.py

[aschleif]

Summary

Running run_pcm.py, whether as part of a ReEDS run with Sw_PCM=1 or just on its own with an existing ReEDS run, throws a few errors, including:

• inability to import reeds or any functions from reeds (e.g., from reeds.input_processing import hourly_repperiods)
• relative file paths getting appended because run_pcm.py gets called twice on the HPC
• compile issues in 2_temporal_params.gms because there is no prm.csv file in the PCM-specific inputs_case/stress0 folder
• mismatching columns between the CEM cf_vre.csv and the PCM cf_vre.csv

Technical details

Implementation notes

Adding an prm.csv file could look more like...

ReEDS/postprocessing/run_pcm.py

Lines 217 to 220 in 96e543b

	pd.DataFrame(columns=['rep_period', 'year', 'yperiod', 'actual_period']).to_csv(
	os.path.join(stresspath, 'period_szn.csv'),
	index=False,
	)

instead of...

ReEDS/postprocessing/run_pcm.py

Lines 246 to 251 in 96e543b

	## 2_temporal_params.gms reads stress{stress_year}/prm.csv even with no stress periods,
	## so use the PRM from the stress folder that the restart solve (_t, _iteration) used
	prm_src = os.path.join(casepath, 'inputs_case', f'stress{_t}i{_iteration}', 'prm.csv')
	if not os.path.isfile(prm_src):
	raise FileNotFoundError(f'PRM file for {_t}i{_iteration} not found: {prm_src}')
	shutil.copy(prm_src, os.path.join(stresspath, 'prm.csv'))

Validation, testing, and comparison report(s)

Checklist for author

Details to double-check

• Charge code provided to reviewers
• Included comparison reports for appropriate test cases
• Documentation updated if necessary
• If input data added/modified:
• Code formatting standardized
• Reusable functions used where possible instead of copy/pasted code

General information to guide review

• Zero impact on results of default case
• No large data file(s) added/modified
• No substantive impact on runtime for full-US reference case
• No substantive impact on folder size for full-US reference case
• No change to process flow (runreeds.py, reeds/core/solve/solve.py)
• No change to code organization
• No change to package requirements (environment.yml or Project.toml)

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