## 273 Reputation

19 years, 275 days

## A little closer to your prototype than M...

With a couple changes one can simplify Markiyan Hirnyk's code.  This may be more like what you indicated you want.  The graph will look much better when you run the code.

 > with(plots): with(plottools): f := (psi-(1/2)*Pi)^2+(theta-.5)^2; g := transform((psi, theta) -> [cos(psi)*sin(theta), sin(psi)*sin(theta), cos(theta)]): c:=contourplot(f, psi = 0 .. 2*Pi, theta = 0 .. Pi, contours = [seq(i,i=-1..10)],coloring=["LightGreen",blue],filledregions = true,color=black,numpoints=10000): display(g(c));
 >

## By default, Maple uses RKF45....

@fixedeggs Please read any munerical analysis text's section on the RKF45 method.  This method does not really do piecewise interpolation.  It uses an RK4 method combined with an RK5 method that have the same order of error.  It then combines those two values to get a better estimate and a local error esitimate.

## By default, Maple uses RKF45....

@fixedeggs Please read any munerical analysis text's section on the RKF45 method.  This method does not really do piecewise interpolation.  It uses an RK4 method combined with an RK5 method that have the same order of error.  It then combines those two values to get a better estimate and a local error esitimate.

## Wonder?...

@Markiyan Hirnyk The order is alphabetical, as in the T2 list.  My assumption was that the original questioner is a student and should do some work.

Is it better than giving dictionary form?  You can judge yourself.

## Wonder?...

@Markiyan Hirnyk The order is alphabetical, as in the T2 list.  My assumption was that the original questioner is a student and should do some work.

Is it better than giving dictionary form?  You can judge yourself.

In order to give you a helpful answer, I would like to know the form of your tableau. For eaxample, does it include the slack variables?

## Ok for me...

@kkongelbeck   I do not have a WIN XP machine I can use for this stuff, but I do have XP sr3 as a virtualbox machine.  I do not have any trouble with the 3D plot in that setting.  The plot  maintains its sharpness after rotations.

Have you checked your graphics driver?

Please post the exact code you are using.

If this is a hardware problem, Maplesoft will probably need to know what hardware you have.

While running Maple 17 on an old 1.6GHz single core laptop with 2gb of ram and Win 7 I do not have the types of problems you are describing.  It is rather slow, but it works.

## Your function has a branch cut....

Doug Meade is correct that it would be nice for Maple to work with discontinuities in plot 3d.

You have a special case.  You are plotting a function over the complex plane that has a branch cut.  If you plot it in polar coordinates, you will get a nice plot.  The attached worksheet has that plot.

 > z := expand(r*exp(I*theta));;
 (1)
 > plot3d([Re(z),Im(z),Im(sqrt(z))],r=0..3,theta=-Pi..Pi,view=[-2..2,-2..2,-2..2]);
 >

1)  A list of plots works well.  You can also add other options when you put your plots in a list.

display([p1,p2,p3],scaling=constrained,font=[TIMES,ROMAN,24]);

2)  Order matters when putting plots together with display.  The commands

display([p1,p2]);

and

display([p2,p1]);

can give different results.

1)  A list of plots works well.  You can also add other options when you put your plots in a list.

display([p1,p2,p3],scaling=constrained,font=[TIMES,ROMAN,24]);

2)  Order matters when putting plots together with display.  The commands

display([p1,p2]);

and

display([p2,p1]);

can give different results.

## Lighting in 3d plots...

I would like to see multiple light sources implemented in the 3d plotting routines.  It is supposed to be there, but does not work.

It would be nice to have *.svg output for graphics that contains actual vector graphics.

A late addition:  Proper mesh and *.u3d exports.  One prolem is that the view is not restricted as per the plot command and a second problem is that they cannot be done from command line.

## Oops, my mistake, wrong package....

The combinat package does not use the same seed.  You can use the command

to get a permutation of the first n positive integers.  This would mean using code similar to the following:

`    \code{      \$n=3;            \$seed=range(1000,10000000);      \$pb=maple("RandomTools[SetState](state=\$seed);             [Statistics:-Shuffle([seq(1..\$n)]),Statistics:-Shuffle([seq(1..\$n)])");I hope that is better.`

## Oops, my mistake, wrong package....

The combinat package does not use the same seed.  You can use the command

to get a permutation of the first n positive integers.  This would mean using code similar to the following:

`    \code{      \$n=3;            \$seed=range(1000,10000000);      \$pb=maple("RandomTools[SetState](state=\$seed);             [Statistics:-Shuffle([seq(1..\$n)]),Statistics:-Shuffle([seq(1..\$n)])");I hope that is better.`

## Confirmed...

I tried this on Maple 14, Maple 15, and Maple 16 using 64bit Linux.  My results are the same.  It works except in Maple 16.

I also tried sending the output to a file and got the same blank plot. The commands I used are attached.

This looks like a bug that needs to be fixed.

ImplicitPlots3d2.mw

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