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WFDB_getframe

Usage: DATA = WFDB_getframe(NSPF);  
  DATA = WFDB_getframe(NSPF, NF);  
  DATA = WFDB_getframe(NSPF, NF, TSTART);  
Input: NSPF: number of samples per frame  
  NF: (optional) number of frames to read  
  TSTART: (optional) frame number of the first frame to read  
Output: DATA: sample value(s)  

This function reads frames from open input signals. It is very similar to WFDB_getvec, and differs only when reading multifrequency records, which it neither interpolates nor decimates; rather, it returns all sample values for each data frame.

For example, if there are two signals, and signal 0 is sampled twice as fast as signal 1, each frame contains two samples of signal 0 followed by one sample of signal 1, so NSPF is 3 (two plus one). Suppose that we run:

{\tt DATA = WFDB_getframe(3, 5, 10)}

This loads five frames (frame numbers 10 through 14) into DATA, which will be organized as:

   [signal 0, sample 20]  [signal 0, sample 21]  [signal 1, sample 10]
   [signal 0, sample 22]  [signal 0, sample 23]  [signal 1, sample 11]
   [signal 0, sample 24]  [signal 0, sample 25]  [signal 1, sample 12]
   [signal 0, sample 26]  [signal 0, sample 27]  [signal 1, sample 13]
   [signal 0, sample 28]  [signal 0, sample 29]  [signal 1, sample 14]


next up previous contents
Next: WFDB_putvec Up: Reading and Writing Signals Previous: WFDB_getvec   Contents
George B. Moody 2005-06-02