Chris@15: 
Chris@93: module yetilab.stream.syntheticstream;
Chris@15: 
Chris@93: str = load yetilab.stream.stream;
Chris@93: vec = load yetilab.block.fvector;
Chris@93: block = load yetilab.block.block;
Chris@15: 
Chris@19: generated rate generator seconds =
Chris@19:     str.monoStream {
Chris@15:         var position = 0,
Chris@19:         len = int(seconds * rate + 0.5),
Chris@19:         rate,
Chris@19:         read count = 
Chris@19:            (rc = min count (len - position);
Chris@15:             result = vec.zeros rc;
Chris@15:             for [0..rc-1] do i:
Chris@15:                 result[i] := generator ((position + i) / rate)
Chris@15:             done;
Chris@15:             position := position + rc;
Chris@20:             block.block result),
Chris@20:         close = \(),
Chris@19:         };
Chris@16: 
Chris@20: sinusoid rate freq seconds =
Chris@20:     generated rate (sin . (* (freq / (2*pi * rate)))) seconds;
Chris@16: 
Chris@20: whiteNoise rate seconds =
Chris@20:     generated rate \((Math#random() * 2.0) - 1.0) seconds;
Chris@16: 
Chris@16: precalculated rate data is number -> ~double[] -> 'a =
Chris@20:    (n = vec.length data;
Chris@19:     str.monoStream {
Chris@16:         var position = 0,
Chris@19:         len = n,
Chris@19:         rate,
Chris@19:         read count = 
Chris@19:            (rc = min count (len - position);
Chris@26:             result = vec.rangeOf data position rc;
Chris@16:             position := position + rc;
Chris@20:             block.block result),
Chris@20:         close = \(),
Chris@19:     });
Chris@15: 
Chris@15: {
Chris@19:     generated, precalculated, sinusoid, whiteNoise,
Chris@15: }
Chris@15: