Hey guys,

I have a problem with this code:

d := Array(1 .. 15);

for i to s1 do

for c2 to 15 do

if `mod`(c2+(J+H)*(`mod`(1/(H+1), A[i])), A[i]) = 0 then d[c2] := d[c2]+l(A[i]) else d[c2] := d[c2]end if

end do

end do;

d;

The problem is that my code stops running when I encounter that `mod`(1/(H+1), A[i]) doesn`t have an modular inverse. What I would like to have is that the loop just continues and does nothing when my array when it encounters an error.

Hope you can help me!

The limit of

G := N -> sum(1/N*numtheory[sigma](k)/k,k=1..N ) 

as N -> infinity should be Pi^2/6. However

eval( G(N), N=infinity );

returns 0.

Can anyone explain this puzzling behaviour?

As stated, contourplot3d is not displaying contours. Even in the Maple Help examples the contours are not displayed in the help screen.

In this example:

contourplot3d(-5*x/(x^2+y^2+1), x = -3 .. 3, y = -3 .. 3, filledregions = true);

which is directly from Maple Help, the surface is plotted (with boxed axes), but no contours appear.

When I try

contourplot3d(-5*x/(x^2+y^2+1), x = -3 .. 3, y = -3 .. 3);

the plot shows nothing except boxed axes.

I've also tried

plot3d(-5*x/(x^2+y^2+1), x = -3 .. 3, y = -3 .. 3, contours=6);

and the surface shows but without countours. Furthermore, the Maple scripts that worked previously in earlier versions (showing contours via plot3d) now do not show contours in Maple 18. This occurs on both Win 7 and Win 8 laptops.

Thanks!

Hello everybody

I am working on the bending of FGM plate, and I just used maple for the calculation functions of my problem of the bending of FGM plates.

Can any from the members of mapleprimes one help me to write Navier's equation include below for the bending of the plate because I am new in using Maple 18

alfa=m*pi/a, beta=n*pi/b with m=1,3,5..100 and n=1,3,5...100

Thank's for all 

Aslam-u-Alikum, want to write the following in Maple please help

psi[1]:=psi[1,0];

psi[2]:=psi[1,1];

psi[3]:=psi[1,2];

psi[4]:=psi[1,3];

psi[5]:=psi[2,0];

psi[6]:=psi[2,1];

psi[7]:=psi[2,2];

psi[8]:=psi[2,3];

PhD (Scholar)
Department of Mathematics

with(plots)

inequal((2*c-1)/(3*c-1),c=0..1.5,Alpha=0..1)

with(plots)

inequal((2*c-1)/(3*c-1),c=0..1,Alpha=0..1)

Why are the results of the two orders above so different???

A bug in the function of inequal???

i am solving 3 ODE with boundary condition.. with boundary condition

b.mw

Maple Worksheet - Error

Failed to load the worksheet /maplenet/convert/b.mw .

Download b.mw

then i got this error

Error, (in dsolve/numeric/bvp) initial Newton iteration is not converging

i dont know where i need to change.. could you help me..

Dear Friends,

My present problem is to calculate the coefficients  

of ODES based on the experiment data. In order to simulate the actual experiment, a set of  is given with . Then the experiment data (yexp) can be calculated. Finally, the least-squares method (lsq) is used to calculate the coefficient values. Now the NLPSolve function can be used. However, the globalsolve can’t run.

If it is convenient for you, wish you can solve it.

Code:

restart;
cdm_ode := diff(y1(t), t) = c0*(y6(t)*(1-y3(t))/(s0*(1-y4(t)*(1-y5(t)))))^n/(1-y2(t)), diff(y2(t), t) = ks*y2(t)^(1/3)*(1-y2(t)), diff(y3(t), t) = h1*(1-y3(t)/h2)*c0*(y6(t)*(1-y3(t))/(s0*(1-y4(t)*(1-y5(t)))))^n/(sigma*(1-y2(t))), diff(y4(t), t) = (1/3)*kp*(1-y4(t))^4, diff(y5(t), t) = A*B*y1(t)^(B-1)*c0*(y6(t)*(1-y3(t))/(s0*(1-y4(t)*(1-y5(t)))))^n/(1-y2(t)), diff(y6(t), t) = y6(t)*c0*(y6(t)*(1-y3(t))/(s0*(1-y4(t)*(1-y5(t)))))^n/(1-y2(t));

tol_t := 3600;
sol := dsolve([cdm_ode, y1(0) = 0, y2(0) = 0, y3(0) = 0, y4(0) = 0, y5(0) = 0, y6(0) = 175], numeric, range = 0 .. tol_t, output = listprocedure, parameters = [c0, n, sigma, s0, ks, h1, h2, kp, A, B]);

sol(parameters = [5.7*10^(-6), 10.186, 175, 200, 5*10^(-8), 10000, .269, 1.5*10^(-7), 1.5, 2]);

t := [seq(i^2, i = 0 .. 50, 1)];

y1data := subs(sol, y1(t));
 
y1exp := [seq(y1data(t[i]), i = 1 .. 51)];

err := proc (c0, n, s0, ks, h1, h2, kp, A, B) local y1cal, y1val, lsq; sol(parameters = [c0, n, 175, s0, ks, h1, h2, kp, A, B]); y1cal := subs(sol, y1(t)); y1val := [seq(y1cal(t[i]), i = 1 .. 51)]; lsq := add((y1val[i]-y1exp[i])^2, i = 1 .. 51); lsq end proc;

with(Optimization);
val := NLPSolve(err, 10^(-8) .. 10^(-4), 2 .. 20, 150 .. 250, 10^(-2) .. 1, 100 .. 20000, 10^(-5) .. .4, 10^(-5) .. 1, .5 .. 2, 1 .. 10);
GlobalSolve(err, 10^(-10) .. 10^(-4), 2 .. 20, 150 .. 250, 0 .. 1, 100 .. 15000, 0 .. .5, 0 .. 1, .5 .. 2, 1 .. 5);

Error, (in GlobalOptimization:-GlobalSolve) `InertForms` does not evaluate to a module

Presentations of the first national congress of civil engineering developed at the University Cesar Vallejo. From 10 to 12 November 2014.

CONIC_UCV.pdf

(in spanish)

Lenin Araujo Castillo

Physics Pure

Computer Science

Hi. I need to test if a variable is a dot-product of "anything"-s (usually it is quantum operators).
I try the following

restart; 
with(Physics); 
Physics:-Setup(mathematicalnotation = true); 
Physics:-Setup(anticommutativeprefix = psi); 
ap1 := Physics:-Creation(psi, 1, notation = explicit); 
am1 := Physics:-Annihilation(psi, 1, notation = explicit); 
ap2 := Physics:-Creation(psi, 2, notation = explicit); 
am2 := Physics:-Annihilation(psi, 2, notation = explicit);

z1 := ap1.am1.ap2:
type(z1, ('`.`')(anything));

and get

false

whereas

z2 := a*b*c; 
type(z2, (':-`*`')(anything));

returns

true

I studied ?type,structured and other sources but didn't find any answer.

I am a Masters of Chemistry student at Leeds University and my project involes producing undirected graphs that look like 2D shapes to represent models of molecules for other student users e.g. if there are 6 atoms it will draw a hexagon shape with each vertices as an atom. It is meant to know what graph to draw by asking them questions in maplet pop-up style windows. To do this I have to ask questions in the pop-up windows like "How many atoms in your molecule?" with a drop down box numbering 2-25 as the possibilities.

The problem I am having is getting Maple to relate the answers to these questions on the maplets to the shape (undirected graph) I want it to draw. It displays the answer in the worksheet as for example; ["12"] but I don't know how to ask maple to recognise this number as meaning anything for making the graph.

Is there anyone who knows about using maplets that could have a chat with me about this?

Thanks! From Megan