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n := 3;
Digits := 10;
R_const := 8.314;
currentdir();
const := [1, 1, 1];
b := 20;
W := readdata("data20.txt", 2);
W := [seq([W[i, 2], W[i, 1]], i = 1 .. nops(W))];
Tempset := seq(W[i, 1], i = 1 .. nops(W));
Rateset := seq(W[i, 2], i = 1 .. nops(W));
Temp := [seq(W[i, 1], i = 1 .. nops(W))];
pdata := plots[pointplot](W, color = red);
pdata;

h[5] := 1;
h[4] := 8.5733287401;
h[3] := 18.059016973;
h[2] := 8.6347608925;
h[1] := 0.2677737343;
p[5] := 1;
p[4] := 9.5733223454;
p[3] := 25.6329561486;
p[2] := 21.0996530827;
p[1] := 3.9584969228;
r := x -> local m; exp(-x)*add(h[m]*x^(m - 1), m = 1 .. 5)/(x*add(p[m]*x^(m - 1), m = 1 .. 5));

q := (i, x) -> -Temp[1]*exp(-E_sim[i]/(R_const*Temp[1])) + E_sim[i]*r(E_sim[i]/(R_const*Temp[1]))/R_const + x*exp(-E_sim[i]/(R_const*x)) - E_sim[i]*r(E_sim[i]/(R_const*x))/R_const;

for i to n do
    R[i] := [seq(1 - exp(-A_sim[i]*const[i]*q(i, Temp[j])/b), j = 2 .. nops(Temp))];
end do;
for i to n do
    Der[i] := [seq(c_sim[i]*A_sim[i]*const[i]*exp(-E_sim[i]/(R_const*Temp[j]))*(1 - R[i][j]), j = 1 .. nops(Temp) - 1)];
end do;
Deriv := add(Der[i], i = 1 .. n);
model := [seq([Temp[i], Deriv[i]], i = 1 .. nops(R[1]))];
objective := add((W[i, 2] - model[i, 2])^2, i = 1 .. nops(Temp) - 1);
with(GlobalOptimization);
infolevel[GlobalOptimization] := 3;
Results := GlobalOptimization[GlobalSolve](objective, {add(c_sim[i], i = 1 .. 3) <= 1}, c_sim[1] = 0.05 .. 0.06, c_sim[2] = 0.85 .. 0.88, c_sim[3] = 0.05 .. 0.6, E_sim[1] = 33880 .. 33890, E_sim[2] = 40220 .. 41230, E_sim[3] = 23230 .. 23235, A_sim[1] = 2453 .. 2455, A_sim[2] = 190 .. 192, A_sim[3] = 1830 .. 1832, timelimit = 7200);
          [GetLastSolution, GlobalSolve, Interactive]

Results := [Float(undefined), [A_sim[1] = 2454.85789978944, 

  A_sim[2] = 190.143107633747, A_sim[3] = 1831.19959951461, 

  E_sim[1] = 33883.8826959700, E_sim[2] = 40796.6139830241, 

  E_sim[3] = 23230.4022199775, c_sim[1] = 0.0558944062681716, 

  c_sim[2] = 0.851532317382881, c_sim[3] = 0.0845465106500359]]


DEV_perc := 100*sqrt(Results[1]/(nops(Temp) - 3*n))/max(Rateset);
       DEV_perc := Float(undefined) + Float(undefined) 

Unsolved for Maple?

Thanks for reading.

I am just evaluating Maple 2021 under Windows 10 and I have something strange happening when I press F1 for Help or I select Maple Help in Help Menu. The first time the help window will appear but if I close it then impossible to view it again by pressing F1 or by selecting it in the Help menu. Also the same for other choices in the help menu like

Maple Help F1
Maple Portal
Study Guides
What's New

But any choices inside On the web will always work.

I am using Windows 10 latest release in french and the keyboard layout in ENG I don't think it is related but just in case someone ask me.

Have you notice the same problem ?

When I use piecewise like this

W :=piecewise(beta>=-Pi/2 and beta<=-Pi/2+Pi/200,1+eps/sin(Pi/200)+eps*cos(Pi/200)/sin(Pi/200)*sin(beta),
     
beta>=-Pi/2+Pi/200 and beta<=Pi/2,1+eps/sin(Pi/200)-eps*cos(Pi/200)/sin(Pi/200)*sin(beta),
      1+eps*(1+cos(beta)));

 

and eval the beta as following,

G:= eval(R,beta=(arctan(diff(f(x,y),y), diff(f(x,y),x))));

the calculation does not run well...because of the undefined

[[-eps sin(t_atan2((&PartialD;)/(&PartialD;y) pho(x,y),(&PartialD;)/(&PartialD;x) pho(x,y))),t_atan2((&PartialD;)/(&PartialD;y) pho(x,y),(&PartialD;)/(&PartialD;x) pho(x,y))<-Pi/2],[undefined,t_atan2((&PartialD;)/(&PartialD;y) pho(x,y),(&PartialD;)/(&PartialD;x) pho(x,y))=-Pi/2],[(eps cos(Pi/200) cos(t_atan2((&PartialD;)/(&PartialD;y) pho(x,y),(&PartialD;)/(&PartialD;x) pho(x,y))))/(sin(Pi/200)),t_atan2((&PartialD;)/(&PartialD;y) pho(x,y),(&PartialD;)/(&PartialD;x) pho(x,y))<-(99 Pi)/200],[undefined,t_atan2((&PartialD;)/(&PartialD;y) pho(x,y),(&PartialD;)/(&PartialD;x) pho(x,y))=-(99 Pi)/200],[-(eps cos(Pi/200) cos(t_atan2((&PartialD;)/(&PartialD;y) pho(x,y),(&PartialD;)/(&PartialD;x) pho(x,y))))/(sin(Pi/200)),t_atan2((&PartialD;)/(&PartialD;y) pho(x,y),(&PartialD;)/(&PartialD;x) pho(x,y))<Pi/2],[undefined,t_atan2((&PartialD;)/(&PartialD;y) pho(x,y),(&PartialD;)/(&PartialD;x) pho(x,y))=Pi/2],[-eps sin(t_atan2((&PartialD;)/(&PartialD;y) pho(x,y),(&PartialD;)/(&PartialD;x) pho(x,y))),Pi/2<t_atan2((&PartialD;)/(&PartialD;y) pho(x,y),(&PartialD;)/(&PartialD;x) pho(x,y))]]

Finally, when W is brought into the following formula for calculation, 

R:=   
-M*ElementInt( test(x,y)*((1-co(x,y))*Ha+co(x,y)*Hb))
     +M*ElementInt( test(x,y)*noise)
+M*gamma*(-ElementInt( W^2*( nab(test(x,y))[i] &t nab(f(x,y))[i])))
              +ElementInt( diff(W^2,beta)/2 * ( diff(test(x,y),x)*diff(f(x,y),y)
              -diff(test(x,y),y)*diff(f(x,y),x))):

 

the following error message will appear.

Error: Division by zero at (1)

 

I mentioned a similar problem just recently, but after two days of continuous attempts, I couldn't find a solution.
Look forward to receiving a reply.......

Hello, 

i would like to continue to work on a code which was done With CodeBuilder some years ago.

i often like to print my code to be able to read without any computer.

Problem : the print function on a worksheet with several coderegion doesn t work well.

1) Do you have some ideas to circumvet this issue ,

2) i m thinking about using a text éditor which can give a nice printing with maple. Emacs is far to much complex for me. Consequently, i havé seen that some of you have testéd Sublime text. I think that it may be a good alternative. Do you have ideas about simple text editor that i can use to edit maple code ?
 

thank you for your help 

hi, I wonder why this output is empty because I tried to get solution below partial equation:

restart;
with(PDEtools);
pe := diff(u(t, x, y), t) = u(t, x, y) - diff(u(t, x, y), x $ 2) - diff(u(t, x, y), y $ 2) + (1 + u(t, x, y)*I)*abs(u(t, x, y))*u(t,x,y)^2;                                  
inc := u(0, x, y) = cos(Pi*x/50) - cos(Pi*x/150)*I;
sys := [pe, inc];
   

pdsolve(sys);
 

end after this pdsolve(sys); Maple doesn't show anything

thanks in advance

The last several times that I've tried to use the Delete As Spam feature I've gotten an error message Error Generating Page, and the spam was not deleted. Anyone know what's happening? 

We give a line (D) and a point A located at a distance AH=h from D. A constant angle of magnitude alpha pivots to its apex A and we call B and C the points where its sides cut the line D. Let O be the center of the circle circumscribed to the triangle ABC.
Demonstrate that the B and C tangents to the O circle keep a fixed direction. 
Here is my code which don't work for slopes are not equal.

restart; with(plots): with(geometry):unprotect(D):
_EnvHorizontalName := 'x':_EnvVerticalName := 'y':
line(D, y = (1/2)*x-1); point(A, 5, 5); PerpendicularLine(lp, A, D); h := distance(A, D); intersection(H, D, lp);
alpha := (1/16)*Pi;
rotation(lp1, lp, (1/6)*Pi, 'clockwise', A); rotation(lp2, lp1, (1/6)*Pi-alpha, 'clockwise', A); FindAngle(lp1, lp2); evalf(%);
intersection(B, D, lp1); intersection(C, D, lp2);
triangle(T, [A, B, C]);
circumcircle(Elc, T, 'centername' = OO);
TangentLine(tgB, B, Elc); TangentLine(tgC, C, Elc);
evalf(slope(tgB)); evalf(slope(tgC));
dr := draw([D(color = blue), lp(color = red), Elc(color = green), A, B, C, T(color = black), H, tgB, tgC], printtext = true);

display([dr], axes = none, scaling = constrained);
Fig := proc (k) local dr, Elc, B, C, lp1, lp2; global D, A, lp, H, alpha; geometry:-rotation(lp1, lp, (1/6)*Pi+k, 'clockwise', A); geometry:-rotation(lp2, lp1, (1/6)*Pi-alpha+k, 'clockwise', A); geometry:-intersection(B, D, lp1); geometry:-intersection(C, D, lp2); geometry:-triangle(T, [A, B, C]); geometry:-circumcircle(Elc, T, 'centername' = OO); geometry:-TangentLine(tgB, B, Elc); geometry:-TangentLine(tgC, C, Elc); dr := geometry:-draw([D(color = blue), lp(color = red), Elc(color = green), A, B, C, T(color = black), H, tgB, tgC], printtext = true); plots:-display([dr], axes = none, scaling = constrained) end proc;
iframes := 10;

display([seq(Fig((1/12)*Pi+i/(10*iframes)), i = 1 .. iframes)], insequence, scaling = constrained);
How to improve this code ? Thank you.

In an answer to an earlier question

https://mapleprimes.com/questions/232067-Error-Invalid-Neutral-Operator

I inadvertently used the "Insert Contents" link - AND IT WORKED

Anybody know how long this has been fixed?

Hi everyone, i want to draw 3d graphics of fractional solution with given by Mittag Leffler function in cantor sets. I want to see like this graphic. I added maple file. Thanks in advance.

3D_graphic.mw3D_graphic.mw

Dear all

I tried to used insert code edit region, to write many subcodes 

but no return varibales names.

example, x:=3;

when I run the code, I get only the number affected to x, I would like to get 

x:=3

No_return_variable.mw

Thank you 

 

 

Why is Maple 2020 in "abcapps.cloud.com" different from Maple 2020 in apps.abc.edu? I am connecting to maple 2020 in two different ways to the school where I work. The schools name is, say, "abc". The first version of Maple 2020 has two arrows at the top. The second arrow is the "upload" arrow and allows me to upload a file from my home computer the my folder at school.
The second version of Maple 2020 has no such arrows. Both versions allow me to get my Maple cloud working for local loading and saving Maple files. How can I upload a Maple file to my Maple cloud from my home computer in the second Maple 2020 version in apps.abc.edu? Or, how can I upload a file to my Maple cloud in any way from my home computer?
By the way, the second Maple 2020 version is coming from Microsoft's Remore Desktop Web Client. It look like it has its own navigation bar at the top.

Thank you!

mapleatha

I defined x(t) and y(t) with units; motion in gravity, motion in y-direction with constant velocity, motion in x-direction as motion with constant acceleration.

x := t -> 10*Unit(('m')/'s'^2)*t^2;

y := t -> 50*Unit(('m')/('s'))*t;

plot([x(t), y(t), t = 0*Unit('s') .. 5*Unit('s')]);

Error, (in plot) invalid terms in product: 0 .. 5*Units:-Unit(s)

It works fine if I remove the units.

Also I can plot graph for x(t) and for y(t) with units, but not graph for [x(t), y(t)]

How to solve the Linear first-order partial differential equation by the Lagrange method. Suppose u and v are dependent variables and x,y,z are independent variables of a partial differential equation of the form:

dx/f(x,y,z)=dy/g(x,y,z)=dz/h(x,y,z)=du/k(x,y,z)=dv/s(x,y,z). I need its solution in the form of u and v . How to find it ?

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