Dear all!

I am facing problem to find the solution of system of linear equations as attached for different values of alpha, please the see the attachment and fix my problem

Equations.mw

Thanks in advance

Hi there,

I know for a given 2x2 system of differential equations, it is possible for maple to plot a phase portrait on x-y plane (or a graph with directions and arrows).And this is also possible in a 3x3 system by choosing 2 variables / the plane of projection by including the code scene=[x(t),y(t)] (on x-y plane) .

My question is:

given a system of 3x3 differential equations,like

dx/dt = f(x(t),y(t),z(t))

dy/dt = g(x(t),y(t),z(t))

dz/dt = h(x(t),y(t),z(t)),

how could I produce a 3D vector field of the system? (with arrows)

Thanks!

Good day!

I am working to solve a double series (LP  minimization) problem of the form 

z = add(add(x[i,j]*y[i,j]*z[j], j=1..6), i=1..3).

However, this returns a set [ ]. 

Since LPSolve does not operate on a set (removing the brackets manually will enable LPSolve to obtain the solution), can anyone suggest what is wrong with the structure of this z-equation? x, y are matrices and z is a column vector.

Thanks!

If I insert a hyperlink to a website, it works fine when I'm in Maple, but when I export my Maple to pdf, the hyperlink is not clickable anymore.

I've tried using both Windows' "Microsoft Print to PDF", Maple's own "Export to PDF", "cutepdf" as well as MacOS "Save to PDF". Is there a way of doing this?

Best wishes

Hey any one can help? I calculated the characteristical Polynom of my Matrix M:

-(lambda-2)^2*(544-lambda^9-328*lambda^7-16*cos(x-y)+6*cos(x-y)*lambda+6*cos(x+y)*lambda-408*cos(y)*lambda^2-408*cos(x)*lambda^2+540*cos(y)*lambda+540*cos(x)*lambda-28*cos(y)*lambda^4-28*cos(x)*lambda^4+152*cos(y)*lambda^3+152*cos(x)*lambda^3+2*cos(y)*lambda^5+2*cos(x)*lambda^5-256*cos(y)+17232*lambda^2-256*cos(x)-7852*lambda^5+17768*lambda^4+2088*lambda^6+28*lambda^8-16*cos(x+y)-23632*lambda^3-5844*lambda)

now I want to solve the second part of the polynomial with lambda^9 but maple gives me the RootOf-function

_Z^9-28*_Z^8+328*_Z^7-2088*_Z^6+(-2*cos(y)-2*cos(x)+7852)*_Z^5+(28*cos(y)+28*cos(x)-17768)*_Z^4+(-152*cos(y)-152*cos(x)+23632)*_Z^3+(408*cos(y)+408*cos(x)-17232)*_Z^2+(-12*cos(x)*cos(y)-540*cos(y)-540*cos(x)+5844)*_Z+32*cos(x)*cos(y)+256*cos(y)+256*cos(x)-544

How can I simplify this expression to solve over lambda.

purpose is to plot all the eigenvalues.

Thank you in advance.

Hello,

Why does the following work as expected...

f__c := proc (x__0, y__0) options operator, arrow; piecewise(x__0^2+y__0^2 <= 1 and (x__0-1)^2+y__0^2 <= 1 and x__0^2+(y__0-1)^2 <= 1 and (x__0-1)^2+(y__0-1)^2 <= 1, 1, not (x__0^2+y__0^2 <= 1 and (x__0-1)^2+y__0^2 <= 1 and x__0^2+(y__0-1)^2 <= 1 and (x__0-1)^2+(y__0-1)^2 <= 1), 0) end proc

But the following does not?

cnd := x__0^2+y__0^2 <= 1 and (x__0-1)^2+y__0^2 <= 1 and x__0^2+(y__0-1)^2 <= 1 and (x__0-1)^2+(y__0-1)^2 <= 1
f__c := proc (x__0, y__0) options operator, arrow; piecewise(cnd, 1, not cnd, 0) end proc

(Sorry about the lack of formatting, the forum insists my Maple syntax is invalid)

The first one produces the expected result, x__0 and y__0 are treated as variables in the condition (i.e. f__c(a, b) returns the same piecewise function with x__0 replaced with a and y__0 replaced with b); the second one does not (i.e. f__c(a, b) returns the piecewise function, still with x__0 and y__0 in the condition, and never gets evaluated).

Dear all

I have a system of PDes, the code i think it's well writte but when I use pdesolve i have no solution obtained.

Maybe I must add something else

Many thinks

sysPDes.mw

I am defining, 

f(x):= x-> diff(g(x),x)/(1+g(x))

Here g(x)<<1 and I am looking for series expansion, 1/(1+g(x)) = 1- g(x) + g(x)^2 etc.

But I cannot get this by using series(f(x),g(x)=0) or other options.

Thanks,

Rahul

Is there a way to remove the parentheses around y'(t)?

Thank you!

mapleatha
 

proc() local a := 0, b := 1;
  print(proc(x::uneval) x := 1 end proc(a));
  print(proc(x::uneval) x := b end proc(a))
end proc();
                               1
Error, (in unknown) illegal use of a formal parameter

Why doesn't the second nested procedure keep a unevaluated?

With Typesetting level set to Maple Standard, x->(f@g)(x) is displayed as x->f@g(x), which is wrong because composition has lower precedence than function application.

sum((-1)^k/k^(1/2), k = 2 .. infinity);
Error, (in polylog) numeric exception: division by zero

how can filter data im maple 18 befor used in draw plot? i need simple example

this is plot of f(x)=x² (by used maple18) ,how can me change (2.5-, 1.5- ,0.5-) in x-axis to true?

Anybody know how to compute coding for eigenvalues for basic reproduction number using the next generation matrix?

I dont know how to compute coding for eigenvalues. 

Coding_Basic_Reproduction_Number.mw