% WFDB_setcfreq(CFREQ);
%
% Set the counter frequency, in Hz. Use WFDB_setcfreq before creating a '.hea'
% file.  The effect of WFDB_setcfreq is nullified by later invoking any of the
% functions that read header files. If CFREQ is zero or negative, the counter
% frequency is treated as equivalent to the sampling frequency.
%
% CFREQ: Counter frequency.
%
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