expseg — Trace a series of exponential segments between specified points.
ares expseg ia, idur1, ib [, idur2] [, ic] [...]
kres expseg ia, idur1, ib [, idur2] [, ic] [...]
ia -- starting value. Zero is illegal for exponentials.
ib, ic, etc. -- value after dur1 seconds, etc. For exponentials, must be non-zero and must agree in sign with ia.
idur1 -- duration in seconds of first segment. A zero or negative value will cause all initialization to be skipped.
idur2, idur3, etc. -- duration in seconds of subsequent segments. A zero or negative value will terminate the initialization process with the preceding point, permitting the last-defined line or curve to be continued indefinitely in performance. The default is zero.
These units generate control or audio signals whose values can pass through 2 or more specified points. The sum of dur values may or may not equal the instrument's performance time: a shorter performance will truncate the specified pattern, while a longer one will cause the last-defined segment to continue on in the same direction.
Note that the expseg opcode does not operate correctly at audio rate when segments are shorter than a k-period. Try the expsega opcode instead.
Here is an example of the expseg opcode. It uses the file expseg.csd.
Example 282. Example of the expseg opcode.
See the sections Real-time Audio and Command Line Flags for more information on using command line flags.
<CsoundSynthesizer> <CsOptions> ; Select audio/midi flags here according to platform ; Audio out Audio in -odac ;;;RT audio out ; For Non-realtime ouput leave only the line below: ;-o expseg.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> ; by Kevin Conder, additions by Menno Knevel 2021 sr = 44100 ksmps = 32 nchnls = 2 0dbfs = 1 instr 1 kcps = cpspch(p4) ; p4 = frequency in pitch-class notation. kenv expseg 0.01, p3*0.25, 1, p3*0.75, 0.001 ; amplitude envelope. kamp = kenv a1 oscili kamp, kcps outs a1, a1 endin </CsInstruments> <CsScore> i 1 0 0.5 8.00 i 1 1 0.5 8.01 i 1 2 0.5 8.02 i 1 3 2.0 8.03 e </CsScore> </CsoundSynthesizer>