i am new user in maple .i want to calculate eigenvalues of a symmetrix matrix to find max or min value but i usually face a error code ' (in simpl/max) complex argument to max/min'

i know that a symmetrix matrix have real eigenvalues.

for example:
restart:with(LinearAlgebra):with(GraphTheory):interface(rtablesize=infinity):
SeidelMatrix:=proc(G::Graph) local J,B,A,S;
J:=Matrix(1..NumberOfVertices(G),1..NumberOfVertices(G),shape=constant[1]):
B:=IdentityMatrix(NumberOfVertices(G)):
A:=AdjacencyMatrix(G):
S:=J-B-MatrixScalarMultiply(A,2):
convert(S,Matrix,shape=symmetric,datatype=float):
return S:
end proc:
E:=sort(eval(Eigenvalues(SeidelMatrix(CycleGraph(7)),output='list'))):
(min,max)(E);
Error, (in simpl/min) complex argument to max/min: (1/3)*(-28+(84*I)*3^(1/2))^(1/3)+(28/3)/(-28+(84*I)*3^(1/2))^(1/3)-1/3
 

I am trying to evaluate the following summation which gives the result 0. But I think answer is not correct.
 

Download zero.mw

A lot of efforts I performed to obtained the right results, somehow I remain sucessful but the results are not exactly same as expected. I request you to kindly see at the christoffel symbol. I also sent the right results.

some_mistakes_in_christoffel.mw

you can see the right results in the given below attachment

right_christoffel_symbols.pdf

as you can comprare the results of both file. the obtain crystoffel are not same as the requied.

is it possible to change ODE to PDE?

the ODE has diff(a(t),t) and diff(b(t),t)

how to convert to diff(t, a), diff(t, b) ?

Is there a built-in function in Maple 2015 that identifies and prints prime numbers in a specified integer range?

Hi

How can I write and solve a dirac_delta function in maple, for example in below equations:

F[0]:=0;
F[1]:=a;
F[2]:=b;

eq1:=sum((k-m+2)*(k-m+1)*F[k-m+2]*Dirac[m-1], m = 0 .. k);

eq2:=(k+1)*F[k+1]-Dirac[k];

for k from 0 to 10 do
F[k+3]:=solve(F[k+3]=(eq1+eq2)/((k+3)*(k+2)*(k+1)),F[k+3]);
end do;

Hi everybody,

I'm kind of new to Maple and i'm trying to solve a system of trigonometric equations inequality as follow:

f:= {((2*a*sin(S)*cos(S)^(2)))/(1-sin(S)^(3))<1,90> S>-90,a>1};

solve(f,{a,S});
Error, (in PiecewiseTools:-Convert) unable to convert
 

How can I solve the system?

Thanks a lot.

Since I am a very recent Maple user, I do not know why I obtained a wrong answer with the following two comands:

Exp:= Psi(rho(x,t),theta(x,t));
                  Psi(rho(x, t), theta(x, t))
Exp1:= diff(Exp,t);
     / d           \                                  
     |--- rho(x, t)| D[1](Psi)(rho(x, t), theta(x, t))
     \ dt          /                                  

          / d             \                                
    + |--- theta(x, t)| Psi(rho(x, t) + 1, theta(x, t))
          \ dt            /                                
 

Can someone, please, help me?

Thank you.

I am using Maple to model Gaussian Wave Packets and the do loop creates an array of plots. I want to animate these plots to show the movement of the wave packet and was wondering if there is a way to animate the array or perhaps another way to produce the animation. 

Hi,

I have a function "L" which is mentioned in the worksheet. I want to obtain equation of motion by solving Euler-Lagrange equation. How I can do this by maple? Have Maple an instruction to solve Euler-Lagrange equation?        ELEOM.mw

how to add two algebaric equations? I have two equation (1) and (2). i simply wrote (1) + (2) instead of adding the eqautions i got result is 3. i think there is some mistake of writng text for calling equation that was in bold. 

adding_two_equations.mw

I am trying to evaluate the following triple integral but it takes much time so i kill the job.

Download int_maple_prime2.mw

Maple newbie here.

I do not understand why algsubs do not replace the symbol in the denominator in the following example, but does replace it in the numerator. This is on Maple 2017 on windows 7

Here is the expression

sol := u(x, t) = Sum((2*cos((1/2)*Pi*_Z1)+
       2+4*(-1)^(1+_Z1))*sin(Pi*_Z1*x/L)*
       exp(-k*Pi^2*_Z1^2*t/L^2)/(Pi*_Z1), 
       _Z1 = 1 .. infinity);

I wanted to replace _Z1  with n

But algsubs will not replace _Z1 in the denominator as seen in this screen shot but subs does:

From help, my impression is that algsubs is superset of subs. Only case where algsubs will not do what subs does is, according to help:

But There is no indexed names here? 

Can someone please explain why algsubs fails to do the substitution in the denominator in this example?

I am trying to evaluate the following function for which I am getting a result 0. I just need to make sure the approach as well as result is correct or not. Thanks in advance. 
 

Download int(maple_prime).mw