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bugs in wg opcodes

Date1999-03-01 22:40
FromAndre Bartetzki
Subjectbugs in wg opcodes
Hi,

this is a collection of waveguide opcode bugs and/or manual errata that I
found during the last weeks.
(Manual pdf-Version 3.50, Mills Csound perf 3.51 (PPC) and IRIX Csound 3.51 (SGI))

1. ar wgpluck2 iplk,xam,icps,kpick,krefl

A krefl value of 1 means no reflection at all and 0 is total reflection
(therefore this is an absorption coefficient). The manual says the opposite.
(there was recently a short thread on this problem)

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2.  ar wgflute kamp,kfreq,kjet,iatt,idetk,kngain,kvibf,kvamp,ifn [,iminfreq]

kfreq accepts no k-rate, even if iminfreq has a reasonable value.

Csound resp. perf prints this message if there is a k-rate kfreq:

PERF ERROR: No base frequency for flute

FATAL ERROR: terminated perf.

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3. ar wgbrass kamp,kfreq,iatt,kvibf,kvamp,ifn [,iminfreq]

This line (similar to the manual example)

a1      wgbrass 20000, 440, 0.1, 6.1, 0.05, 1

gives

error:  insufficient required arguments, line 3:
a1  wgbrass 20000, 440, 0.1, 6.1, 0.05, 1
1 syntax errors in orchestra.  compilation invalid

whereas

a1      wgbrass 20000, 440, 0.1, 6.1, 0.05, 1, 200  ; iminfreq = 200

gives

INIT ERROR in instr 1: invalid ftable no. 200.000000
a1  wgbrass 20000   440 0.1 6.1 0.05    1   200 0   

PERF ERROR: No table for Brass

Does that mean that there is an undocumented argument before ifn, for example
an idetk-time similar to the other wg opcodes?

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4. ar wgclar kamp, kfreq,kstiff,iatt,idetk,kngain,kvibf,kvamp,ifn [,iminfreq]

If we have a k-rate kfreq and no iminfreq like in 

kf	line	200,p3,400
a1	wgclar	20000,kf,-0.3,0.1,0.1,0.2,6,0.1,1

then iminfreq should be set automatically to the initial kfreq.
But this doesn't work:

PERF ERROR: No base frequency for clarinet

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5. ar shaker kamp,kfreq,kbeans,kdamp,knum,ktimes [,idecay]

A line similar to the example given in the manual results in

error:  too many input args, line 13:
a1  shaker  20000, 400,8, 0.999, 0,100,0
1 syntax errors in orchestra.  compilation invalid

(see also Javier Ruiz' message some weeks ago)

BTW, what does a frequency of a shaker really mean??

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6. a1 mandol kamp,kfreq,kpluck,kdetune,kgain,ksize,ifn [,iminfreq]

Every trial to use mandol with the suggested values leads to a crash!

-----------

I think most of these are "bugs" in the manual descriptions of the opcodes. (?)


Andre

--------------------------------------------------
Andre Bartetzki http://www.kgw.tu-berlin.de/~abart
Studio fuer elektroakustische Musik http://www.kgw.tu-berlin.de/~abart/Steam/steam.html
Hochschule fuer Musik Berlin http://www.hfm-berlin.de

Tel. +49-30-4726629
Tel. +49-30-203092488