Hi

The following code is time consuming. Please improve the code, if it is possible. Thanks for taking your time

restart;

T := time(): 
M := 50: 
Digits := 30: 
L := 500: 
R := (1/2): 
nu := 0.3: 
Em := 0.70e11: 
N := 1: 
Ec := 0.380e12: 
E:= Em*(1-(y/h+1/2)^N)+Ec*(y/h+1/2)^N: 
X :=(int(E*(z+(1/2)*R), [z = y-(1/2)*R .. 0, y = -(1/2)*R .. (1/2)*R]))/(int(E, [z = y-(1/2)*R .. 0, y = -(1/2)*R .. (1/2)*R])): 
beta := Pi^2/L^2: 
G := E/(2*(1+nu)): 
phi := add(b[n]*y^n, n = 0 .. M): 
Eq := diff(phi, y$2)+(diff(E, y))*(diff(phi, y))/E+((diff(E, y$2))/E-((diff(E, y))/E)^2)*phi-2*beta*(1+nu)*(phi-1): 
st := [seq(coeftayl(Eq, y = 0, j), j = 0 .. M-2)]: 
for k to M-1 do 
b[k+1] := solve(st[k], b[k+1]) 
end do: 
phi := subs(y = y-X, phi): 
phi := subs(solve({eval(phi, y = -(1/2)*R+X), subs(y = f, phi)}, {b[0], b[1]}), phi): 
f := piecewise(`and`(z >= -R, z <= 0), z+(1/2)*R+X, -z+(1/2)*R+X): 
Digits := 4: 
int(phi*G, [z = y-(1/2)*R .. 0, y = -(1/2)*R .. (1/2)*R], numeric)+int(phi*G, [z = 0 .. -y+(1/2)*R, y = -(1/2)*R .. (1/2)*R], numeric);

Time = Time()-T;

Note that the calculation of the integration requires alot of time. Both returns a similar result (calculation of an integration is sufficient)

Hello,

I'm trying to use a text editor (notepad++) to developp a code in Maple. 

Before creating a package, i would like to test step by step the different procedures that i create.

To do so, i would like to launch some procedures created in notepad++. I guess i have to call the maple kernel from notepad++. How can i do to call the maple kernel from a editor (in my case notepad++) ?

Next, would it be possible for me to test directly on a worksheet a procedure that i have been created in notepad and launched from notepad ?

I thank you in advance for your help.

hi! lately I'm thinking about animating complex phase portraits so I tried something like this:

restart;
with(plots);
f := (a, z) -> (z*a - 1)/(z^2 + z + 1);
display(seq(densityplot(proc(x, y) local res; res := evalhf(argument(f(1/100*a, y + x*I))); return res; end proc, -4 .. 4, -4 .. 4, axes = boxed, view = [-2 .. 2, -2 .. 2], restricttoranges, colorstyle = HUE, style = surface, grid = [201, 201]), a = 1 .. 200), insequence = true);
 

but this takes a long time to load. Do you how can we optimizate this code?

Hello,

In a maple code, i have the symbol dollar as an the last argument of a procedure.

What is the meaning of the use of dollar symbol as an argument in a maple procedure ?

Thank you for your help.

Hi,

I just upgraded to Maple 2021 and started getting strange results - similar calculations seemed to work in Maple 2020.

I am looking at correlated bivariate normal distributions. When doing a fully symbolic verification of the normalization, I get an incorrect result of infinity. I also get strange results when integrating over a circular region, but the normalization seemed to be a very elementary calculation.

Maybe someone can check this make sure I'm not losing my marbles. I've attached a worksheet.

Thanks.

Bivariate_Gaussian.mw

hi, do you know how can we plot analogy situation from this post:

https://mathematica.stackexchange.com/questions/100051/dynamic-epicycles/100108#100108

I really like simplicity and beauty of the idea from:

https://www.mapleprimes.com/posts/206167-Procedures-For-Two-Animations

and I wonder if it would be possible to add a third rolling circle similarly not including such long code from first page.

thanks in advance

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

Hello,

does Maple have a PDE solver? I want to solve the following inhomogeneous case of the heat equation:

diff(u(t,x,y,z),t)=k*Laplacian(u(t,x,y,z))+l*u(t,x,y,z)+m

with boundary conditions u(t,0,y,z)=u(t,L,y,z)=u(t,x,0,z)=u(t,x,L,z)=u(t,x,y,0)=u(t,x,y,L)=0. The initial condition is not fixed, as I want to try different cases. It will probably be some sinusoidal spatial function. I would prefer an analytic solution but I could live with a numerical one. If not in three spatial dimensions then even a solution with one dimension would be useful. I would appreciate any help.

Thank you.

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);