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Time to frequency domain conversion#

Apply a time to frequency domain conversion using a 1D Fast Fourier Transform (FFT) along the time axis of an input 3D cube.

Description#

This script uses xrft.xrft.fft to compute the forward FFT. xrft is build on xarray, dask and numpy and preserves netCDF metadata during computations.

Command line interface#

The script needs a single netCDF (3D) as input (in time domain):

There are two options to run the script. We recommend using the CLI entry point like: 

>>> 12_cube_apply_FFT /path/to/cube.nc --params_netcdf /path/to/config.yml [optional parameters]
Alternatively, the script can be executed using the (more verbose) command: 
>>> python -m pseudo_3D_interpolation.cube_apply_FFT /path/to/cube.nc \
      --params_netcdf /path/to/config.yml [optional parameters]

Optionally, the following parameters can be specified:

  • --help, -h: Show help.
  • --params_netcdf: Path of netCDF parameter file (YAML format). Required!
  • --prefix: Prefix for new netCDF variable and coordinate.
  • --compute_real: Compute FFT assuming real input and thus discarting redundant negative frequencies.
  • --filter {lowpass | highpass | bandpass}: Optional filter to apply prior to FFT computation.
  • --filter_freqs: Filter corner frequencies (in Hz).
  • --verbose {LEVEL}, -V: Level of output verbosity (default: 0).
Last update: Monday, 03 July 2023 at 09:46:51