Broken example in vco2ift

[hlolli]

<CsoundSynthesizer>
<CsOptions>
; Select audio/midi flags here according to platform
-odac  ;;;realtime audio out
;-iadc    ;;;uncomment -iadc if realtime audio input is needed too
; For Non-realtime ouput leave only the line below:
; -o vco2ift.wav -W ;;; for file output any platform
</CsOptions>
<CsInstruments>

sr = 44100
ksmps = 32
nchnls = 2
0dbfs  = 1

; user defined waveform -2: fixed table size (64), number of partials
; multiplier is 1.4
itmp    ftgen 2, 0, 64, 5, 1, 2, 120, 60, 1, 1, 0.001, 1
ift     vco2init -2, 2, 1.4, 4096, 4096, 2


instr 1

icps = p4
ifn  vco2ift icps, -2, 0.5	;with user defined waveform
print ifn
asig oscili 1, 220, ifn		; (-2), and sr/2 bandwidth
     outs asig, asig

endin
</CsInstruments>
<CsScore>

i 1 0 2 20
i 1 3 2 2000
i 1 6 2 20000

e
</CsScore>
</CsoundSynthesizer>

returns

0dBFS level = 32768.0
--Csound version 6.14 (float samples) Aug  1 2019
[commit: 69f84761cbe4e7e79be1cd1e99a0f0d45eb09499]
libsndfile-1.0.25
CsoundObj_compileCSD...
csoundCompileCsdText...
STARTING FILE
Creating options
Creating orchestra
closing tag
Creating score
sample rate overrides: esr = 44100.0000, ekr = 1378.1250, ksmps = 32
setting dummy interface
midi channel 1 using instr 1
midi channel 2 using instr 1
midi channel 3 using instr 1
midi channel 4 using instr 1
midi channel 5 using instr 1
midi channel 6 using instr 1
midi channel 7 using instr 1
midi channel 8 using instr 1
midi channel 9 using instr 1
midi channel 10 using instr 1
midi channel 11 using instr 1
midi channel 12 using instr 1
midi channel 13 using instr 1
midi channel 14 using instr 1
midi channel 15 using instr 1
midi channel 16 using instr 1
0dBFS level = 1.0
ftable 2:
INIT ERROR in instr 0 line 19: function table is NULL, check that ibasfn is available

 from file *string* (1)
ift	vco2init	-2	2	1.4	4096	4096	2	
header init errors

this could be a problem with the opcode itself or parameters in the manual, no sure.

[jpffitch]

Changing the second arg to vco2init from 2 to 3 seems t improve things. not sure if this is correct

[vlazzarini]

the example for vco2init appears to use that formula of ift, ift+1, which indicates it's right. The manual text is pretty obtuse on that parameter, maybe it could be better explained.