The fourier operator performs the fourier transformation or the inverse fourier transformation of all input fields. If the number of timesteps is a power of 2 then the algorithm of the Fast Fourier Transformation (FFT) is used. If the input stream infile consists only of complex fields, then the fields of outfile, computed by cdo -f ext fourier,1 -fourier,-1 infile outfile are the same than that of infile. For real input files see function retocomplex.
Usage
cdo_fourier(ifile, epsilon = NULL, ofile = NULL)
Arguments
- ifile
String with the path to the input file.
- epsilon
INTEGER - -1: forward transformation; 1: backward transformation
- ofile
String with the path to the output file.
Value
Operators that output one or more files return a character vector to the
output files.
Operators that output an indefinite number of files return a string with the
basename of the files.
Operatos that don't return filenames return a character vector with the
string output.
Note
Complex numbers can only be stored in NetCDF4 and EXTRA format.