kinsnum -- number of the instrument to be reported
active returns the number of active instances of instrument number insnum/kinsnum. As of Csound4.17 the output is updated at k-rate (if input arg is k-rate), to allow running count of instr instances.
Here is a simple example of the active opcode. It uses the files active.orc and active.sco.
Example 23. Simple example of the active opcode.
/* active.orc */ ; Initialize the global variables. sr = 44100 kr = 4410 ksmps = 10 nchnls = 1 ; Instrument #1 - a noisy waveform. instr 1 ; Generate a really noisy waveform. anoisy rand 44100 ; Turn down its amplitude. aoutput gain anoisy, 2500 ; Send it to the output. out aoutput endin ; Instrument #2 - counts active instruments. instr 2 ; Count the active instances of Instrument #1. icount active 1 ; Print the number of active instances. print icount endin /* active.orc */
/* active.sco */ ; Start the first instance of Instrument #1 at 0:00 seconds. i 1 0.0 3.0 ; Start the second instance of Instrument #1 at 0:015 seconds. i 1 1.5 1.5 ; Play Instrument #2 at 0:01 seconds, when we have only ; one active instance of Instrument #1. i 2 1.0 0.1 ; Play Instrument #2 at 0:02 seconds, when we have ; two active instances of Instrument #1. i 2 2.0 0.1 e /* active.sco */
Its output should include lines like this:
instr 2: icount = 1.000 instr 2: icount = 2.000
Here is a more advanced example of the active opcode. It displays the results of the active opcode at k-rate instead of i-rate. It uses the files active_k.orc and active_k.sco.
Example 24. Example of the active opcode at k-rate.
/* active_k.orc */ ; Initialize the global variables. sr = 44100 kr = 4410 ksmps = 10 nchnls = 1 ; Instrument #1 - a noisy waveform. instr 1 ; Generate a really noisy waveform. anoisy rand 44100 ; Turn down its amplitude. aoutput gain anoisy, 2500 ; Send it to the output. out aoutput endin ; Instrument #2 - counts active instruments at k-rate. instr 2 ; Count the active instances of Instrument #1. kcount active 1 ; Print the number of active instances. printk2 kcount endin /* active_k.orc */
/* active_k.sco */ ; Start the first instance of Instrument #1 at 0:00 seconds. i 1 0.0 3.0 ; Start the second instance of Instrument #1 at 0:015 seconds. i 1 1.5 1.5 ; Play Instrument #2 at 0:01 seconds, when we have only ; one active instance of Instrument #1. i 2 1.0 0.1 ; Play Instrument #2 at 0:02 seconds, when we have ; two active instances of Instrument #1. i 2 2.0 0.1 e /* active_k.sco */
Its output should include lines like:
i2 1.00000 i2 2.00000