User`s guide

SdfYdata
Syntax int SdfYdata (short fn, long offset, short dataNo,
short rowNo, short colNo, long scanNo, long pnts,
short dataType, float far *y);
Returns an integer(short) of zero or minus one. A return of 0 indicates no error; a return of
-1 indicates an error.
This function reads Y-axis data from an open SDF file and puts it in an array, where y is the pointer to the
array, and fn is the number of the open SDF file (for details, see SdfOpen).
The offset is the number of data points to skip before reading the data. One situation where an offset is
useful is if you are reading data in multiple passes. If you don’t want to use an offset, specify an offset of
zero.
The dataNo selects the data result that you want to examine–most instruments have only 1 data result,
therefore, you will usually specify zero for this parameter, which selects the first data result. In general,
rowNo selects the channel, scanNo selects the trace (in the case of waterfall or spectrogram
measurements), and colNo is not used. A rowNo of zero selects channel 1 and a scanNo of zero selects
the first trace. For further details, see chapter 2.
Note All parameters are zero based. Therefore, for parameters such as dataNo, rowNo,
colNo, and scanNo, zero selects the first item, as described in the above paragraph.
Furthermore, you must include all parameters. For unused parameters,
specify zero.
The pnts are the number of data points you want to read. For example, a complex value is 2 points. To
determine the number of data points in the record, see ‘’Reconstructing a Trace’’ in appendix B.
Using SDF Data with C Programs
SdfYdata
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