> with(DEtools);
> with(plots);
> a := diff(y(x), x) = e(x)^(-0.1e-1*xy^2);

> g := dfieldplot(a, y(x), x = -8 .. 8, y(x) = -8 .. 8, color = e(x)^(-0.1e-1*xy^2));
Error, (in DEtools/dfieldplot) extra unknowns found: xy

how to solve this?
>
>

Hello,In short: I try to get the eigenvalues of a 16x16 complex matrix with one variable B__z. I know, the vales are very small (~10^-24), so I multiply with 10^24 and collect B__z. Now, when I use Eigenvalues(H) [H is the matrix] the result is just wrong:

test.mw

(same with original values) - compared to Mathematica which solves and plots in about 1 sec:

Where is the problem? What should I do? Any suggestions?

Hello,

first of all, this is my very fist question in this forum, so please excuse some formal mistakes I may make...

Using Maple 18.01 on Windows 7 64bit

To the topic: I want to calculate the eigenvalues of a complex matrix like this (just as an example):

M := Matrix(2, 2, {(1, 1) = a+2.5*I, (1, 2) = 1-I*a, (2, 1) = 4, (2, 2) = a})

When I try to calculate

Eigenvalues(M)

I get

Error, (in LinearAlgebra:-Eigenvalues) expecting either Matrices of rationals, rational functions, radical functions, algebraic numbers, or algebraic functions, or Matrices of complex(numeric) values

Strange, because if I replace the "2.5" with just "2", so an integer instead of a float, I get results:

I don't understand this strange behavior, since Mathematica i.e. calculates everything just fine...:

Thanks in advance for any suggestions.

How to get the equations of circles A, B, C, such as circle A with center (1,1) is drawn in the first quadrant.

Circle B with radius 2 and circle C are placed so that each circle is tangent to the other 2 circles and the x-axis.

THe 3 circles are on the first quadrant.

1) do it with Maple

2) do it by hand

3) draw the figure

Regards

solve([b+c = a*a1+b*a4+c*a7, a+c=a a2+b a5+c a8, a+b = a*a3+b*a6+c*a9], [a1,a2,a3,a4,a5,a6,a7,a8,a9]);

how to assume a1 to a9 are 0 or 1

and find one of possible matrix is

Expected Result := Matrix([[1,1,0],[1,0,1],[0,1,1]]);

Hi everyone,

I am exploring the physics package a bit. However, in the documentation I didn't find anything about how to setup operator-ket relations like:

A | l,m,n > = f(l,m,n) | g(l,m,n), h(l,m,n), z(l,m,n) >

The Creation and Annihilation operators were the only predefined ones I found.

Cheers

NOh

Greetings,

I am a Maple 15 Student Edition user on both Windows and Linux. I wonder if it is possible to see the actual command send to Maple when I click on a particular entry in the right click context menu. If it is possible to do so, how can I have it displayed in document/worksheet mode? Does it matter if I am inputting in 1D or 2D?

Thanks in advance

Hi there,

first post. I am a beginner both with Maple and this forum, so please forgive my mistakes. Just here to learn.

I could not successfully use the Maple editor here, so the code goes as plain text, although I also attach the code: MapleSimulation_test.mw.

I am trying to simulate the function below for certain values of the parameters, but when executing the loop, Maple prints just R. Can anyone tell me where my error is, please?

f := .25; g := 1; R[0] = 5; R[1] = 4.8; nDays := 30;

lambda1:=(1 - f + sqrt((1 - f) + 4*g*f)*1/2;

lambda2:=(1 - f - sqrt((1 - f) + 4*g*f)*1/2;

       -lambda2*R[0] + R[1]
k1:=--------------------------;
       lambda1 - lambda2

       lambda2*R[0] - R[1]
k2:=-------------------------;
      lambda1 - lambda2

R:=n-> k1*lambda1^n + k2*lambda2^n

for n from 2 to nDays
do R:=evalf(subs(n=%,R));
od;

Hi everyone,

I have to create a double wishbone suspesione model that can be edited by different users, only introducing some reference point values (called Hard Points). So I need some tool that, in some way, passes from the entered reference point values to the actual values of the bodyframes link. 

I found an already done model (from this link) that seems to be perfect to me because contains an attached Maple document that does exactly what I need working on the base of symbolic parameters applied to the MapleSim model. Now my problem is that I need to deeply change the model and so having the possibility to change the parameter set and insert for example nex parameters. But when I try to do that some problems come out with the Maple document: the syntax of the nex parameter set is different from the default (in the sense of already built in the model I downloaded) one and there are some syntax errors. Below I'll put a screenshot of the error.

under the XData code line, you can also see the syntax of one of the parameters that is very long and complicated: below I'll insert another image from which it can be seen the syntax with the original parameter set.

Now if you another idea for solving the initial problem, that would be great! Instead do you have an idea on how to fix the problem with the downloaded model? In my opinion there is a different MapleSim version problem, in the sense that could be thatn the model I downloaded has been done in another MapleSim version in which the parameter set syntax was different.

is it possible to assume element of matrix 0 or 1

how to write?

after write this, is it possible to display possible matrices which each element is 0 or 1

with(LinearAlgebra):
GetRing := proc(sol)
ringequation := 0;
mono1 := 0;
for j from 1 to 3 do
mono1 := 1;
for i from 1 to nops(sol[1][j]) do
mono1 := mono1*op(i, sol[1][j]);
od:
ringequation := ringequation + mono1;
od:
return ringequation;
end proc;
M := Matrix([[a1,a2,a3],[a4,a5,a6],[a7,a8,a9]]);
sys := a*b+a = GetRing(MatrixMatrixMultiply(Matrix([[a,b,c]]), M));
solve(sys);

I am running a huge symbolic problem in Maple 18. At the moment, I dont even know if there is enough computational power to suceed the computation.

However, I'd like to save a progress. And maybe to continue computation later.

Is there any way to save progress?

Hi Maple friends.

For the function x^3-3*x^2-24*x+8, I right-click and choose "Evaluate at a point", and then enter the x value to evaluate.

Maple ouputs 

eval( x^3-3*x^2-24*x+8, [x = -2]);

36

But I would like to evaluate at x=-2,4,6, 9.

How can I quickly do this, without having to right-click for all points? If there is any Maple employee reading this, please provide a function in the context menu to evaluate at more than one point. It becomes very tedious when I have 10 functions and need to evaluate up to 10 points for each function.

Thanks in advance.

N := 8;

b := 2 ∗ P i;
data := [];
for n f rom 0 to N do
data := [op(data), [n ∗ b/N, sin(n ∗ b/N)]];
od;

Since exact points are not needed, changed the loop (and reinitialize) to:

data := [];

for n from 0 to N do
data := [op(data), [evalf(n ∗ b/N), sin(evalf(n ∗ b/N))]];
od;

Modify the second example so that it can be used to graph the sin function
over any interval from a to b. (You should suppress the output from the for-loop in your
example, so that you do not fill up the worksheet with an unwieldy amount of output.)

Hi all

How can I construct following triangular block matrix?

where

and

P is (N*M)*(N*M) and E and H are M*M matrices. t_f is known constant.

thanks in advance

Mahmood   Dadkhah

Ph.D Candidate

Applied Mathematics Department