MaplePrimes - answers and comments on Question, polarplot -- parametric

Polar

gkokovidis — Wed, 14 May 2008 00:59:39 Z

The relationship between a polar equation r and parametric equations is that x = r cos(θ) and y = r sin(θ).

>restart:

>with(plots):

>polarplot([sin(2*theta),theta,theta=0..2*Pi]);

>r1:=sin(2*theta);
>x1:=r1*sin(theta);
>y1:=r1*cos(theta);
>plot([x1,y1,theta=0..2*Pi]);

Regards,
Georgios Kokovidis

Dräger Medical

alla — Wed, 14 May 2008 01:20:29 Z

Sorry, Georgios, neither of your suggestions work. I get a four-leat rose in both cases.

Allan

alla — Wed, 14 May 2008 01:35:12 Z

Georgios, you had it right except that you wrote sin(2*theta) instead of 2 sin(theta).

Alla

dharr — Wed, 14 May 2008 01:35:32 Z

Georgios has slipped the 2 into the wrong place; you want

polarplot([2*sin(theta),theta,theta=0..2*Pi]);

gkokovidis — Wed, 14 May 2008 03:44:33 Z

Thank you for the correction, sometimes what I see and what I type are not aligned. I need to copy and paste instead of transcribing.

Regards,
Georgios Kokovidis

Dräger Medical