MaplePrimes - answers and comments on Question, How do i solve drawing a polar coordinates function?

one way

Kamel Boughrara — Fri, 16 Dec 2011 23:02:16 Z

with(plots):

F:=(r,theta)->piecewise(r<>0,sin(6*r)/(6*r),r=0,1);

# 3d plot

plot3d(F(r,theta),theta=0..2*Pi,r=-1..1, coords=cylindrical);

2d plot

polarplot(F(0,theta), theta=0..2*Pi);

z_cylindrical

Preben Alsholm — Fri, 16 Dec 2011 23:42:28 Z

Be aware that Maple's cylindrical coordinates are interpreted the following way (quoting the help page for plot3d,coords from Maple 12, as it happens):

"... when using cylindrical coordinates, Maple expects the command to be of the following form:
plot3d(r(theta,z), theta=a..b, z=c..d, coords=cylindrical); "

Thus if you want the (to me) usual way z = F(r,theta), you either parametrize x,y,z by r and theta as is first done below, or you introduce z_cylindrical coordinates as is also shown below (taken from the help page again).

restart;
F:=piecewise(r=0,1,sin(6*r)/(6*r));
plot3d([r*cos(theta),r*sin(theta),F],theta=0..2*Pi,r=0..2,axes=boxed);

addcoords(z_cylindrical,[z,r,theta],[r*cos(theta),r*sin(theta),z]);

plot3d(F,r=0..2,theta=0..2*Pi,coords=z_cylindrical,axes=boxed);

Correction

Markiyan Hirnyk — Fri, 16 Dec 2011 23:48:11 Z

Warning, coordinates already exists, system redefined.

@Markiyan Hirnyk Ok, thanks

Kamel Boughrara — Sat, 17 Dec 2011 01:10:09 Z

@Markiyan Hirnyk

Ok, thanks

thank you

englanderghost — Sat, 17 Dec 2011 05:30:52 Z

thank you