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stmnodecount

Returns the number of nodes in the graph of a runner.

Syntax

kcount = stmnodecount(irunner)
kcount stmnodecount irunner

Initialization

irunner -- a runner handle, returned by stminstance.

Performance

kcount -- the number of nodes. Node ids go from 0 to kcount - 1.

This opcode only reads the runner. Any number of instruments can use it at the same time.

Examples

A scripted run of a small graph. It prints, for each control period, the current node and the graph clock as read before stmadvance, the request made, and what stmadvance returned. Each control period lasts 10 ms. It uses the file stm-trace.csd.

A scripted run showing every advance status.
<CsoundSynthesizer>
<CsOptions>
-n -d -m0
</CsOptions>
<CsInstruments>
sr = 48000
ksmps = 480
nchnls = 1
0dbfs = 1

; A scripted run of a small graph. Each control period lasts 10 ms.
; The trace shows what stmadvance returns for each kind of request,
; and how the graph clock moves.

; Idle -> Play, Play -> Play (self edge), Play -> Hold, Hold -> Play or Idle
builder:i = stmcreate()
stmaddnode(builder, "Play")    ; id 0
stmaddnode(builder, "Idle")    ; id 1
stmaddnode(builder, "Hold")    ; id 2
stmentry(builder, "Idle")      ; start from Idle instead of id 0
stmaddedge(builder, "Idle", "Play")
stmaddedge(builder, "Play", "Play")
stmaddedge(builder, "Play", "Hold")
stmaddcondedge(builder, "Hold", ["Play", "Idle"])
definition:i = stmcompile(builder)
gi_runner@global:i = stminstance(definition)

instr 1
  r:i = gi_runner
  cycle:k init 0
  cycle += 1

  if cycle == 1 then
    printks("%d nodes, %d edges: %s %s %s\n", 0, stmnodecount(r), stmedgecount(r), \
            stmnodename(r, 0), stmnodename(r, 1), stmnodename(r, 2))
    printks("cyc node   id  tick  time  nodetime  request       status from to\n", 0)
  endif

  ; read the node and the clock before stmadvance
  node:S = stmcurrent(r)
  id:k = stmcurrentid(r)
  tick:k = stmtick(r)
  time:k = stmtime(r)
  nodetime:k = stmnodetime(r)

  request:S = strcpyk("-")
  if cycle == 2 then
    stmnext(r, "Play")
    request = strcpyk("Play")
  elseif cycle == 3 then
    stmnext(r, "Idle")              ; there is no Play -> Idle edge
    request = strcpyk("Idle")
  elseif cycle == 4 then
    stmnext(r, "Play")              ; self edge
    request = strcpyk("Play")
  elseif cycle == 5 then
    stmnext(r, "Hold")              ; two different requests
    stmnext(r, "Idle")
    request = strcpyk("Hold+Idle")
  elseif cycle == 6 then
    stmnext(r, stmnodeid(r, "Hold"))  ; request by id
    request = strcpyk("id of Hold")
  elseif cycle == 8 then
    stmreset(r, 1)                  ; back to the entry node, Idle
    request = strcpyk("reset")
  endif

  status:k, from:k, to:k = stmadvance(r)
  printks("%3d %-5s %3d %5d %5.2f %9.2f  %-12s %6d %4d %2d\n", 0, \
          cycle, node, id, tick, time, nodetime, request, status, from, to)

  if cycle == 9 then
    turnoff
  endif
endin
</CsInstruments>
<CsScore>
i 1 0 1
e
</CsScore>
</CsoundSynthesizer>

See also

State Machine Graphs

stmedgecount, stmnodename

Credits

Author: Pasquale Mainolfi
Italy
New in Csound version 7.0
October 2026