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Re: [sc-dev] Buffer.cheby buggy?
this is due to the way chebychev-polynomials work. The first "partial", e.g., is a pure sawtooth. 

http://mathworld.wolfram.com/ChebyshevPolynomialoftheFirstKind.html
is there a bug in the Chebychev Buffer Fill algorithm ? i get a lot of distortion / overtones when trying to use even harmonics ... any clues? 

best, -sciss-


   b = Buffer.alloc( s, 1024, 1 );
   b.sine1([ 1.0 ], true, true, true );   // initial test

(
	{
		var input;
		input = SinOsc.ar( MouseX.kr( 40, 14000, \exponential ));
		Shaper.ar( b.bufnum, input, mul: 0.5 );
   }.play;
)

   // just generate the fundamental ; that's ok
   b.cheby([ 1.0 ], true, true, true );
   // should be one octave but, but distorts
   b.cheby([ 0.0, 1.0 ], true, true, true );
   // ok
   b.cheby([ 0.0, 0.0, 1.0 ], true, true, true );
   // wrong
   b.cheby([ 0.0, 0.0, 0.0, 1.0 ], true, true, true );
   // ok
   b.cheby([ 0.0, 0.0, 0.0, 0.0, 1.0 ], true, true, true );
   // wrong
   b.cheby([ 0.0, 0.0, 0.0, 0.0, 0.0, 1.0 ], true, true, true );
   // ok
   b.cheby([ 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1.0 ], true, true, true );
   // wrong
   b.cheby([ 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1.0 ], true, true, true );
   // ok
b.cheby([ 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1.0 ], true, true, true ); 
   // all odd harmonics ok
b.cheby([ 1.0, 0.0, 1.0, 0.0, 1.0, 0.0, 1.0, 0.0, 1.0 ], true, true, true ); 
   // ok for some reason ?!
b.cheby([ 0.0, 1.0, 0.0, 1.0, 0.0, 1.0, 0.0, 1.0, 0.0 ], true, true, true ); 
   // not ok
   b.cheby([ 0.0, 1.0, 0.0, 1.0, 0.0, 1.0, 0.0 ], true, true, true );


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