smthClmDay - Githubissues

NCAR / geocat-comp

GeoCAT-comp provides implementations of computational functions for operating on geosciences data. Many of these functions originated in NCL and were translated into Python.

https://geocat-comp.readthedocs.io

Apache License 2.0

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smthClmDay #16

Open clyne opened 5 years ago

clyne commented 5 years ago

Port the smthClmDay family of functions, including: smthClmDayTLL, smthClmDayTLLL. The smthClmDay functions calculates a smooth mean daily annual cycle for an array nominally dimensioned (Time,Level,Lat,Lon).

pilotchute commented 3 years ago

From investigation, smthClmDayTLL and smthClmDayTLLL are not fortran functions. They are contained in ncl/ni/src/examples/gsun/contributed.ncl at lines 4543 and 4583 respectively.

Their implementation should be relatively straightforward in python, as they are based on taking an FFT of the input data modifying the result, then performing a backwards FFT.

pilotchute commented 3 years ago

smthClmDayTLL notes: crosslinking https://github.com/NCAR/geocat-comp/issues/17 rmMonAnnCyc since the underlying fftf and fftb are very similar and could benefit from being implemented with both sets of functions in mind.

calls only two external functions:
- ezfftf_n
- ezfftf_n is a direct call to the FFTPACK routine at http://www.netlib.org/fftpack/ezfftf.f
- ezfftb_n
- ezfftb_n is a direct call to the FFTPACK routine at http://www.netlib.org/fftpack/ezfftb.f

pilotchute commented 3 years ago

@hCraker Let's figure out what this actually does, because the description doesn't match the math. If this is covered by fourier_filters.py, we can close this ticket.

erogluorhan commented 2 years ago

@hCraker could you please clarify if we had any progress here or whether we could relate this function to either geocat.comp.climatologies.climatology or geocat.comp.climatologies.climatology_average.