Is there a reason that an angle theta from zero to pi/2 (0 to 90 deg) returns as invalid for an animation range?  I am trying to rotate a vector 2D for visualization.  This is build-up towards a 3d rotating vector in an animation.  

Here is the code: theta is the arrow tip rotation's location via cos(theta), sin(theta) coordinates in a 2D vector.

animate(arrow, [<cos(theta), sin(theta)>, width = [0.05, relative], view = [-1 .. 2, -1 .. 2], color = "blue"], theta = 0 .. Pi/2)

ErrorMessage:  

Error, (in plots/animate) 0 = 0 .. (1/2)*Pi  is an invalid animation range

Thanks In Advance,

Bill

How can this expression sorted in order of the symbol "y"? I want the terms with y locate at the beginnig.

Download sort.mw

As the title, who can help me fix the problem like this

theta:= diff(arctan(y,x)):

W:= piecewise(

         theta>-Pi/2 and theta< -Pi/2+10, 1+A+B*cos(theta),

         theta>-Pi/2+10 and theta< Pi/2-10. 1-A+B*cos(thea)); 

there always plotout the undefined when acrtan(y,x)=Pi/2,

How can I ignore this undefined or define another value for W when acrtan(y,x)=Pi/2

    Dear Fellows
Hoped everything is fine with you. I plotted some contours for a flow model and i want to generate its dat file. Please help me in this regard. Thanks

Attached is a worksheet containing a simple assignment that gives an "illegal use of an object as a name" error. I created the superscripted name in the following way.

1)  type b.

2) click on the Insert|Typesetting|Superscript  item in the insert menu.

3) enter 1 at the cursor in the superscript position.

4)  the result is a name b with superscript 1, but this symbol does not constitute a valid name for an assignment.

Download errorws.mw

How Would I fix that?

Hi 

I forgot how to display the output ar an array i.e. (r,u(r)) (table of data)

I am sure i will find answers here.

a:=-0.1:alpha:=0.2:

dsys:={diff(u(r),r,r)+((1-alpha)/r+r^(alpha-2))*diff(u(r),r)=a};

res1:=dsolve(dsys union {u(0.05)=0,u(1)=0},numeric);

How we can see steps of Laplace transform calculation?

In a thesis by Md. Mohsin Ali at the University of Ontario, he says that ifactor uses multiple threads and presents a graph of measured results.

I ran ifactor with a 100 digit input and do not see mserver using multiple cores in top.  I do see mserver using 100% of a single core.

Am I missing something?

It would be nice to save various animated Maple images from into GIF images, but without the coordinates and the axes. THe same question in anoehr way: Can we plot the original function without any axes or coordinates?

Thank you!

mapleatha

ifactor(1522605027922533360535618378132637429718068114961380688657908494580122963258952897654000350692006139);

kilobytes used=921, alloc=1200, time=0.09
kilobytes used=1325, alloc=5296, time=0.13

...

kilobytes used=107733, alloc=9228, time=6.64

Process Maple segmentation fault (core dumped)

No matter what I do from the keyboard, a core dump is not a reasonable response.

This worksheet animates stereographic projection of a grid on a sphere onto the plane the sphere sits on.

Is there a way to display matching colors in corresponding cells in the two grids?

Stereographic_projection.mw

My question is whether any special interest groups exist in the Maple Cloud?  If so, is there a public listing of these groups?

Hi,

I need to find out how to print the number of row or the numbers on right based only on the combination of the two numbers in first two columns. The external file looks like this:

I have prepared possible combinations of numbers and I need to read the numbers on the right which belongs to this combination. There is no such thing as the sum of two numbers = number of row, so it can't be done this easy.

Can somebody help please? Thanks a lot