Re: [sc-dev] Buffer.cheby buggy?

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this is due to the way chebychev-polynomials work. The first "partial", e.g., is a pure sawtooth.
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http://mathworld.wolfram.com/ChebyshevPolynomialoftheFirstKind.html

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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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