status.i4.v = dio_ftp_default_freq_c(ftp_class.i4.v,

	This routine determines the default frequency for a
	given fast time plot.

	ftp_class	fast time plot class code (constants are in 'ftp')
	time_range	time range in seconds
	default_freq	returned default frequency in Hz

	This function returns ACNET status values as follows:

	OK			success
	DIO_BADARG		invalid fast time plot class or
				time range supplied

	This function requires the following include files:

	diolib_h, ftp_h, acnet_errors_h

	Related functions:

	dio_ftp_class_info_c, dio_can_read_using_ftp_c, dio_can_ftp_c,
	dio_build_ftp_list_c, dio_get_ftp_list_c, dio_get_raw_ftp_list_c,
	dio_get_status_ftp_list_c, dio_cancel_ftp_list_c,
	dio_snapshot_class_info_c, dio_can_read_using_snapshot_c,
	dio_can_snapshot_c, sr_sda_get_ftp_list_c, sr_sda_get_raw_ftp_list_c,

	C/C++ usage:

	int	status;
	int	ftp_class = FTP_CLASS_C290;
	unsigned int	default_freq;
	double	time_range = TIME_RANGE;

	status = dio_ftp_default_freq_c(ftp_class,time_range,&default_freq);