When using Maple 15, sometimes the pagackages and formulas that were previously defined seem to completely drop it.  I'll load packages and assign variables at the beginning of my project, yet after maybe 10 minutes or so, I have to redefine my variables and reload my pacakges.  I have noticed that it happens more often if I try to switch over to the "Text" tab and then back to "Math."  It's very intermittent, Maple will be working just fine churning out graphs,...

Hello.

if I write N[0]:=1; and press enter, I will get the response

N[0] := 1

Now if in my large document I happen to have defined a variable b:=5; then later 

I try to define another variable N[b]:=1; and press enter, I get this response:

N[5] := 2

But N[b] has nothing to do with "b". Why does Maple do this? Is there 

some concept I am missing? In what context is this useful?

many thanks.

Hi, someone insert a .mw file in the mapleprimes answer, but i could not open it. May I know how do i open the worksheet please? It does not show when i click on it. I tried "save target as" it didn't work as well. Please help. Many thanks, Serena Lim

helo to all i want to know how to solve a lp model having 4 decision variables and 4 constraints means how to solve them to get  optimal solution . Plz guide me ,thanks  : )

eq1 := x+y+z+a*t-s = 0;
eq2 := x-y+2*z-t = 1;
eq3 := 2*x-y+t+s = a;
eq4 := 2*x-3*y+z-2*t+2*s = 3;
eq5 := -y+4*z-3*t-s = 0;

solve({eq1, eq2, eq3, eq4, eq5}, {x, y, z, t, s});

I need to solve this system in any case in which the value of a is not 2. If I substitute a by 2, the system is solved, but if I try to solve it like this or if I try to substitute a by any value that is not 2, not even an error appears.

What the hell am I doing wrong? I've...

hi everybody!!

i have tried to (solve /Numerically Solve)  the equation below 

x-(sin(88.61) TAN(286.13)*(45567))/(sqrt(sin(49.12)^2+2 sin(49.12) TAN(14.93) cos(49.12)+2 sin(49.12) TAN(286.13) cos (88.61)

cos(49.12)+2 TAN(14.93)^2 cos(49.12) TAN(286.13) cos (88.61) sin(49.12)+2 TAN(286.13)^2 cos^2 (88.61)^2 cos(49.12) TAN(14.93)

sin(49.12)+TAN(286.13)^2 cos^2 (88.61)^2 TAN(14.93)^2 sin(49.12)^2+TAN(286.13)^2 sin(88.61)^2+TAN(286.13)^2 sin(88.61)^2

HI,

I measured some points. This points are plotted in a graph. Now I want to make a fit on this points.

I now that the fit-function has to be like this:

F = A + B1 x e^(-t/C1) + B2 x e^(-t/C2)

Problem: how can I create a fitting function like that?

The best thing I found is the "spline"-fit, but it doesn't work properly. It has to be one lonely function, not a summary of several functions (like spline).

I have a problem with solving these two equations.

When I put this into maple -> solve([0.4=a*cos(b*8)+3 and 0.2=-a*sin(b*8)*b],[a,b])

It say: "Warning, solutions may have been lost". I don't know what to do.

Dear guys,

recently, I met a problem. I need to compute numerically the Mathieu function of bessel I type and bessel K type(Ie,Io,Ke,Ko or denoted by Ce(-q),Se(q),Fek,Gek etc.). That is the mathieu function could be expanded in the series of the modified bessel function I or K. However, I find the commands in maple is very limited, and a question is coming: how to compute these functions with maple?

Thanks for your attention.

yxxu

why do i get this 

"Error, (in solve) cannot solve expressions with diff(diff(y(x), x), x) for x"

when i input these: 

> restart; with(DEtools); with(plots); with(linalg);
> ode2 := x^2*(diff(y(x), `$`(x, 2)))+x*(diff(y(x), x))+4*y(x) = -2*x+7; bc2 := y(1) = 7, y(4) = -1;

a := 1; b := 4

ic2 := bc2[1], (D(y))(a) = alpha

constraint := lhs(bc2[2])-rhs(bc2[2]); constraint = 0

Hello,

I have a big problem With maple, it's a bit complicated, but I will try to detail. it's been months since I still looking for the solution :

I have a profit function expressed as follows:

Hi,

I am trying to implement some numerical algorithm for an optimal control problem (still).

It involves double cycle. In the inner one two DE systems are solved sequentially and the result is used to update values of some objective function.

This part uses remeber option thanks to pagan  and is ok.

However, in the outer cycle I use the values of this objective function to obtain solution for yet another DE and update ICs for the inner cycle.

Hi,

   The error showed up whenever I tried to do the Maximum Likelihood Estimation with Global Optimization Toolbox.My objective (likelihood ) function f is defined as follows(A1 to A5 are intermediate variables; parameters  are x[1] to x[12]）:

   f := 0;

   for j from 1 by 1 to 21 do

       A1 := exp(x[1]+x[2]*c[j]);

       A2 := exp(x[3]+x[4]*c[j]);

How do I input the integral?

int((x-m^2)/(x+1),x=0..m^2).

Please help me. Thank you.

I'm using Maple to simulate particle collision and interaction (absorption and scattering) and keep tracking its energy until each particle either get absorbed or leaked (Energy less than predefined minimum energy). I also use Maple statistical pacakge. I also need to call MATLAB link to generate histogram in a logarithmically spaced bin, a feature that I could not find anywhere in Maple and I think it is one of the reasons for calculation performance issue.

The problem...