ModVanDerPol ;==================================================================== ; ; Shaun's Modified Van Der Pol non-perturbative forced oscillator. ; After E.Atlee Jackson, Perspectives on non-linear dynamics, Vol. I, 1991. ; ; x' = - y + A * cos(?t) ; y' = x + ?*(1-x*x)*y ; ; ; Ignasi Alvarez, 1998. ; rev. 2005 ; ; p4 = difrerencial de ? per polifon?a. ; p5 = "inversi? de fase" (+1, -1) ; ;==================================================================== ; p4 - frequency addition ; p5 - panning ifreq = p4 ipanL = sqrt(p5) ipanR = sqrt(1-p5) kfreq = <omega> kgain = <gain> kres = <res> kfiltfreq = <freq> kalfa init 2.328041 kmu init 0.557286 kcont init 0 amod init 0 ax init .5 ay init .5 axnew init 0 aynew init 0 afiltL init 0 afiltR init 0 aoutL init 0 aoutR init 0 kfreq = kfreq+ifreq amod phasor kfreq,0 axnew = (-1)*ay+kalfa*amod aynew = ax+ay*kmu*(1-ax*ax) afiltL lowpass2 axnew*kgain,kfiltfreq,kres afiltR lowpass2 aynew*kgain,kfiltfreq,kres aoutL = afiltL aoutR = afiltR blueMixerOut aoutL*ipanL,aoutR*ipanR ax=axnew ay=aynew ;Optionally output to a Display object: ;kax downsamp ax ;kay downsamp ay ;outvalue "kdisplay", 0.5+kax/5 ;outvalue "kdisplax", 0.5+kay/5 omega 43 24 true 1.448863 1545.0 348.97617 140 true 90 186 Omega gain 232 28 true 0.0 10000.0 1692.2822 80 false 260 128 Gain res 333 29 true 1.0 50.0 3.5 80 true 327 127 Filter Resonance freq 222 165 true 20.0 22050.0 372.48 120 true 240 305 Filter Frequency