I still think the use of an array or table is the obvious way as  
others suggested.  Then one lookup like iblack[inotenum % 12] gives  
the result with table
iblack[] fillarray 0,1,0,1,0,0,1,0,1,0,1,0
No need for an UDO
==John ff

Quoting Stefan Thomas <kontrapunktstefan@gmail.com>:

> Ok, I've got it! I will try Your code. Thanks a lot!
>
>
> 2014-05-20 21:24 GMT+02:00 Steven Yi <stevenyi@gmail.com>:
>
>> Hi Stefan,
>>
>> Actually, I'm not sure if that UDO would work as-is, it might return a
>> b-type (boolean) rather than an i-type.  It might work due to the lack
>> of type checking on xout, but whenever I can get to adding that type
>> checking, it'd fail.  You might try something like:
>>
>> opcode is_black_key, i, i
>>    inotenum xin
>>    ival = inotenum % 12
>>    if (ival == 1 || ival == 3 || ival == 6 || ival == 8 || ival == 10) then
>>      ival = 1
>>    else
>>      ival = 0
>>    endif
>>
>>    xout ival
>> endop
>>
>> That way the UDO will return either 1 or 0, depending on if it is a black
>> key.
>>
>> steven
>>
>> On Tue, May 20, 2014 at 3:17 PM, Stefan Thomas
>> <kontrapunktstefan@gmail.com> wrote:
>> > Dear Steven,
>> > I assume the modulo operator (%) does the same like in pyhon, right?
>> > And I would like to understand:
>> > if ival is e.g. 2, what is the value of xout? Or will there by no output
>> of
>> > the opcode?
>> >
>> >
>> > 2014-05-19 18:22 GMT+02:00 Steven Yi <stevenyi@gmail.com>:
>> >
>> >> An array would be a good generic solution.  For one specific to just
>> >> black-key or white key, you might want to write a UDO that checks if a
>> >> note num is a black key.  Something like:
>> >>
>> >> opcode is_black_key, i, i
>> >>    inotenum xin
>> >>    ival = inotenum % 12
>> >>    xout (ival == 1 || ival == 3 || ival == 6 || ival == 8 || ival == 10)
>> >> endop
>> >>
>> >>
>> >>
>> >> On Mon, May 19, 2014 at 12:10 PM, Rory Walsh <rorywalsh@ear.ie> wrote:
>> >> > You could save the note numbers in an array? That wouldn't bloat the
>> >> > code too much.
>> >> >
>> >> > On 19 May 2014 17:06, Stefan Thomas <kontrapunktstefan@gmail.com>
>> wrote:
>> >> >> Dear community,
>> >> >> I want to allocate two different sounds to different midi-keys.
>> >> >> My aim is to get one sound for the black and another sound for the
>> >> >> white
>> >> >> keys.
>> >> >> I've started with the following code which works.
>> >> >> But my question is:
>> >> >> Is the maybe a more confortabe way to do this? If I use my method the
>> >> >> if
>> >> >> condition would be very long!
>> >> >> Here is my code:
>> >> >> <CsoundSynthesizer>
>> >> >> <CsOptions>
>> >> >> -odac -Ma -m0d
>> >> >> </CsOptions>
>> >> >> ; ==============================================
>> >> >> <CsInstruments>
>> >> >>
>> >> >> sr    =    44100
>> >> >> nchnls    =    2
>> >> >> 0dbfs    =    1
>> >> >> gisine ftgen 0,0,2^13, 10, 1
>> >> >> alwayson 1
>> >> >> massign 0, 1
>> >> >> instr 1
>> >> >>     iamp     ampmidi 0.2
>> >> >>     icps     cpsmidi
>> >> >>     inotnum    notnum
>> >> >>     iatt     = 0.01
>> >> >>     idur     = 3
>> >> >>     irel     = 0.1
>> >> >>     aenv     linsegr 0,iatt,1,idur,0,irel,0
>> >> >>     if ( (inotnum == 60) || (inotnum == 62) || (inotnum == 64) ||
>> >> >> (inotnum
>> >> >> == 65) ) then
>> >> >>     aout    poscil    aenv*iamp,icps
>> >> >>     else
>> >> >>     aout    rand    aenv*iamp
>> >> >>     endif
>> >> >>     outs    aout, aout
>> >> >> endin
>> >> >>
>> >> >> </CsInstruments>
>> >> >> ; ==============================================
>> >> >> <CsScore>
>> >> >>
>> >> >> </CsScore>
>> >> >> </CsoundSynthesizer>
>> >> >>
>> >> >>
>> >> >>
>> >> >
>> >> >
>> >> > Send bugs reports to
>> >> >         https://github.com/csound/csound/issues
>> >> > Discussions of bugs and features can be posted here
>> >> > To unsubscribe, send email sympa@lists.bath.ac.uk with body
>> "unsubscribe
>> >> > csound"
>> >> >
>> >> >
>> >> >
>> >>
>> >>
>> >> Send bugs reports to
>> >>         https://github.com/csound/csound/issues
>> >> Discussions of bugs and features can be posted here
>> >> To unsubscribe, send email sympa@lists.bath.ac.uk with body
>> "unsubscribe
>> >> csound"
>> >>
>> >>
>> >>
>> >
>>
>>
>> Send bugs reports to
>>         https://github.com/csound/csound/issues
>> Discussions of bugs and features can be posted here
>> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
>> csound"
>>
>>
>>
>>
>
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