Polar-Kartesisch- Koppelung
Prof. Dr. Dörte Haftendorn: Mathematik mit MuPAD 4 (es ex. in Version 3), Mrz. 06 Update 10.01.07
Web: www.mathematik-verstehen.de www.uni-lueneburg.de/ing-math
Archimedische Spirale:
r:=t->t/4:r(t);
archi:=plot::Polar([r(t),t],t=0..ende,ende=0..20,
LineWidth=1, Mesh=400, LineColor=RGB::Red):
archikart:=plot::Curve2d([t,r(t)],t=0.01..0.01+ende,
LineWidth=1, Mesh=400,ende=0..20, LineColor=RGB::Green):
radius:=plot::Line2d([0,0],[r(t)*cos(t),r(t)*sin(t)],t=0.01..0.01+20):
radiusordi:=plot::Line2d([t,0],[t,r(t)],t=0.01..0.01+20):
plot(archi,radius,archikart,radiusordi,
AnimationStyle=BackAndForth):
Polarparabel
r:=t->t^2/4:r(t);
archi:=plot::Polar([r(t),t],t=-8..ende,ende=-8..8,
LineWidth=1, LineColor=RGB::Red, Mesh=400):
archikart:=plot::Curve2d([t,r(t)],t=-8..ende,ende=-8..8,
LineWidth=1, Mesh=400,LineColor=RGB::Green):
radius:=plot::Line2d([0,0],[r(t)*cos(t),r(t)*sin(t)],t=-8..8):
radiusordi:=plot::Line2d([t,0],[t,r(t)],t=-8..8):
plot(archi,radius,archikart,radiusordi,
AnimationStyle=BackAndForth):
Polarhyperbel
r:=t->1/t: r(t);
archi:=plot::Polar([r(t),t],t=0.01..0.01+ende,ende=0..8,
LineWidth=1, LineColor=RGB::Red, Mesh=400):
archikart:=plot::Curve2d([t,r(t)],t=0.01..0.01+ende,ende=0..8,
LineWidth=1, Mesh=400, LineColor=RGB::Green):
radius:=plot::Line2d([0,0],[r(t)*cos(t),r(t)*sin(t)],t=0.01..0.01+8):
radiusordi:=plot::Line2d([t,0],[t,r(t)],t=0.01..0.01+8):
plot(archi,radius,archikart,radiusordi,ViewingBox=[-1..8.1,-1..4],
Scaling=Constrained, AnimationStyle=BackAndForth):
limit(1/t*sin(t), t = 0)
plotfunc2d(1/t*sin(t))
r:=t->10*sin(t)/t: r(t);
archi:=plot::Polar([r(t),t],t=0..ende,ende=0..20,
LineWidth=1,LineColor=RGB::Red, Mesh=400):
archikart:=plot::Curve2d([t,r(t)],t=0..ende,ende=0..20,
LineWidth=1, Mesh=400, LineColor=RGB::Green):
radius:=plot::Line2d([0,0],[r(t)*cos(t),r(t)*sin(t)],t=0..20):
radiusordi:=plot::Line2d([t,0],[t,r(t)],t=0..20):
plot(archi,radius,archikart,radiusordi,
AnimationStyle=BackAndForth):
Besondere Muschel
r:=t->t*cos(t): r(t);
archi:=plot::Polar([r(t),t],t=0..ende,ende=0..20,
LineWidth=1,LineColor=RGB::Red, Mesh=400):
/*kreis:=plot::Polar([10*cos(t),t],t=0..ende,ende=0..20,
LineWidth=0.5,LineColor=[1,0,1], Mesh=400):*/
archikart:=plot::Curve2d([t,r(t)],t=0..ende,ende=0..20,
LineWidth=1, Mesh=400, LineColor=RGB::Green):
radius:=plot::Line2d([0,0],[r(t)*cos(t),r(t)*sin(t)],t=0..20):
radiusordi:=plot::Line2d([t,0],[t,r(t)],t=0..20):
plot(archi,radius,archikart,radiusordi,
AnimationStyle=BackAndForth):
Kardioide
r:=t->cos(t)+1: r(t);
archi:=plot::Polar([r(t),t],t=0..ende,ende=0..2*PI,
LineWidth=1, LineColor=RGB::Red, Mesh=400):
archikart:=plot::Curve2d([t,r(t)],t=0..ende,ende=0..2*PI,
LineWidth=1, Mesh=400, LineColor=RGB::Green):
radius:=plot::Line2d([0,0],[r(t)*cos(t),r(t)*sin(t)],t=0..2*PI):
radiusordi:=plot::Line2d([t,0],[t,r(t)],t=0..2*PI):
plot(archi,radius,archikart,radiusordi,
AnimationStyle=BackAndForth):
Andere Pascalsche Schnecke
r:=t->cos(t)+1/2: r(t);
archi:=plot::Polar([r(t),t],t=0..ende,ende=0..2*PI,
LineWidth=1, LineColor=RGB::Red, Mesh=400):
archikart:=plot::Curve2d([t,r(t)],t=0..ende,ende=0..2*PI,
LineWidth=1, Mesh=400, LineColor=RGB::Green):
radius:=plot::Line2d([0,0],[r(t)*cos(t),r(t)*sin(t)],
t=0..2*PI,LineWidth=0.5):
radiusbetrag:=plot::Line2d([0,0],[abs(r(t))*cos(t),abs(r(t))*sin(t)],
t=0..2*PI,LineColor=[1,0,1],LineWidth=0.5):
radiusordi:=plot::Line2d([t,0],[t,r(t)],t=0..2*PI,LineWidth=0.5):
plot(archi,radiusbetrag,radius,archikart,radiusordi,
AnimationStyle=BackAndForth):
Berechnung der Tangenten für die Pascalsche Schnecke im Ursprung
solve(cos(t)+1/2=0,t)
tang1:=plot::Function2d(2*PI/3*x,x=-1..1):
tang2:=plot::Function2d(-2*PI/3*x,x=-1..1)
r:=t->cos(t)+1/2: r(t);
archi:=plot::Polar([r(t),t],t=0..ende,ende=0..2*PI,
LineWidth=1, LineColor=RGB::Red, Mesh=400):
archikart:=plot::Curve2d([t,r(t)],t=0..ende,ende=0..2*PI,
LineWidth=1, Mesh=400, LineColor=RGB::Green):
radius:=plot::Line2d([0,0],[r(t)*cos(t),r(t)*sin(t)],t=0..2*PI, LineWidth=0.5):
radiusbetrag:=plot::Line2d([0,0],[abs(r(t))*cos(t),abs(r(t))*sin(t)],t=0..2*PI,
LineColor=[1,0,1], LineWidth=0.5):
radiusordi:=plot::Line2d([t,0],[t,r(t)],t=0..2*PI, LineWidth=0.5):
plot(archi,tang1,tang2,radiusbetrag,radius,archikart,radiusordi,
AnimationStyle=BackAndForth):
Blume
r:=t->cos(2*t): r(t);
archi2:=plot::Polar([r(t),t],t=0..ende,ende=0..2*PI,
LineWidth=1,LineColor=[1,0,0], Mesh=400):
archikart2:=plot::Curve2d([t,r(t)],t=0..ende,ende=0..2*PI,
LineWidth=1, Mesh=400, LineColor=RGB::Green):
radius2:=plot::Line2d([0,0],[r(t)*cos(t),r(t)*sin(t)],t=0..2*PI,
LineWidth=0.5):
radiusbetrag2:=plot::Line2d([0,0],[abs(r(t))*cos(t),abs(r(t))*sin(t)],
t=0..2*PI,LineColor=[0,1,0]):
radiusordi2:=plot::Line2d([t,0],[t,r(t)],t=0..2*PI):
plot(archi2,radiusbetrag2,radius2,archikart2,radiusordi2,LineWidth=0.5,
AnimationStyle=BackAndForth):
dieselbe Viererblume pur
plot(archi2);
Andere Viererblume
r:=t->cos(2*t)^2: r(t);
archi:=plot::Polar([r(t),t],t=0..ende,ende=0..2*PI,
LineWidth=1, LineColor=RGB::Red, Mesh=400):
archikart:=plot::Curve2d([t,r(t)],t=0..ende,ende=0..2*PI,
LineWidth=1, Mesh=400, LineColor=RGB::Green):
radius:=plot::Line2d([0,0],[r(t)*cos(t),r(t)*sin(t)],t=0..2*PI,
LineWidth=0.5):
radiusbetrag:=plot::Line2d([0,0],[abs(r(t))*cos(t),abs(r(t))*sin(t)],
t=0..2*PI,LineWidth=0.5,LineColor=[0,1,0]):
radiusordi:=plot::Line2d([t,0],[t,r(t)],t=0..2*PI):
plot(archi,radiusbetrag,radius,archikart,radiusordi,
AnimationStyle=BackAndForth):
andere Viererblume pur, sie wird anders durchlaufen als die erste Vierenblume
plot(archi);
Beide Blumen zusammen
plot(archi, archi2 , AnimationStyle=BackAndForth):
Fazit: An der fertigen Kurve sieht man den Durchlaufsinn gar nicht.
Wenn man ihn durch die Animation bemerkt, dann kann man ihn mit der karteischen
Koppelung bestens erklären.
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Doppel-Ei
r:=t->cos(1*t)^2: r(t);
archi:=plot::Polar([r(t),t],t=0..ende,ende=0..2*PI,
LineWidth=1, LineColor=RGB::Red, Mesh=400):
archikart:=plot::Curve2d([t,r(t)],t=0..ende,ende=0..2*PI,
LineWidth=1, Mesh=400, LineColor=RGB::Green):
radius:=plot::Line2d([0,0],[r(t)*cos(t),r(t)*sin(t)],t=0..2*PI,
LineWidth=0.5):
radiusbetrag:=plot::Line2d([0,0],[abs(r(t))*cos(t),abs(r(t))*sin(t)],
t=0..2*PI,LineWidth=0.5,LineColor=[0,1,0]):
radiusordi:=plot::Line2d([t,0],[t,r(t)],t=0..2*PI):
plot(archi,radiusbetrag,radius,archikart,radiusordi,
AnimationStyle=BackAndForth):
r:=t->cos(3*t)^2: r(t);
archi:=plot::Polar([r(t),t],t=0..ende,ende=0..2*PI,
LineWidth=1, LineColor=RGB::Red, Mesh=400):
archikart:=plot::Curve2d([t,r(t)],t=0..ende,ende=0..2*PI,
LineWidth=1, Mesh=400, LineColor=RGB::Green):
radius:=plot::Line2d([0,0],[r(t)*cos(t),r(t)*sin(t)],t=0..2*PI,
LineWidth=0.5):
radiusbetrag:=plot::Line2d([0,0],[abs(r(t))*cos(t),abs(r(t))*sin(t)],
t=0..2*PI,LineWidth=0.5,LineColor=[0,1,0]):
radiusordi:=plot::Line2d([t,0],[t,r(t)],t=0..2*PI,LineWidth=0.5):
plot(archi,radiusbetrag,radius,archikart,radiusordi,
AnimationStyle=BackAndForth):