Hi guys. How do I plot the solutionpoint from an optimization as a function of a parameter in an effective way? The problem I'm struggeling with is the following. I'm interested in the optimal E of V := (E,a) -> int(-1/2*E*(-r+E)/r*((1/2*r)^(-1+a)*(1-1/2*r)^(-1+a)/Beta(a,a)),r = E .. 2); for any given a, given 0<>

I am trying to write a procedure that uses LinearAlgebra[SingularValues]. For some reason, the line U,S,Vt := LinearAlgebra[SingularValues](covariance, output=['U','S','Vt']); causes the procedure to give the error message: Error, (in LinearAlgebra:-LA_Main:-SingularValues) invalid output (U) specified However, outside the procedure the same line works perfectly. Any help will be much appreciated!

Hi, I was wondering if there is a way to use Document Components or Maplet Elements from Java? Is there a file that has the library for these components? I use the Netbeans environment, has anyone set up that environment to use Maple libraries? Thanks, Art

I have the initial and boundary conditions: cond := ro(x, 0) = 0, v(x, 0) = 0, {ro(0, t) = 10, ro(40, t) = 20}, {v(0, t) = 10, v(40, t) = 20}; The PDE system is: sys2 := {diff(ro(x, t), t)+diff(ro(x, t)*v(x, t), x) = 0, diff(v(x, t), t)+v(x, t)*(diff(v(x, t), x))+3*ro(x, t)*(diff(ro(x, t), x)) = 0}; I use: sol1 := pdsolve(sys2, {cond}, numeric, time = t, range = 0 .. 40); values := sol1:-value(); ... When I try to see the values I receive the following error: values(40, 20); Error, (in solnproc) unable to compute solution for t>0.: column vector dimension less than length of sparse data

I am trying to calculate the second derivative of a taylor expansion. Could anyone tell me how to enter this command? Thanks Rachel

Can someone point me in the direction to integrate a maple file into a java program? I made a maple file that has a variable and will output a final graph after long calculations.. What I want is a nice java app where the user can simply type in the variable they want, and a graph is displayed in a window? Just a general kick in the butt to the direction for documentation about such a process would be great! Thanks!

Inspired by the post Re: the physics package I decided to have a closer look at the function FeynmanDiagrams. As the Lagrangian I thought I might as well take the QED Lagrangian for a massless spinor field Q[i](X) coupled to an external electromagnetic field A[mu](X):

restart:
with(Physics):
Setup(advanced):
L_QED :=
   +Dagger(Q[i](X)) * Dgamma[4] * Dgamma[mu][i,j] * I * diff(Q[j](X),X[mu])
   +Dagger(Q[i](X)) * Dgamma[4] * Dgamma[mu][i,j] * e * A[mu](X) * (Q[j](X));

Hello, I'am using Maple 11 and have the following problem concerning plots of ODE: ode := M*(diff(x(t), t, t))+K*x(t) = Force; sol := dsolve({ode, x(0) = 0, (D(x))(0) = 0}, numeric); xx := (t) -> rhs(sol(t)[2]); dx := (t) -> rhs(sol(t)[3]); M := 1; K := 4*Pi^2; test := proc (F, t) global Force; Force := F; xx(t) end proc; When I call test(F,t) directly everything works fine: test(2, 2); -2.49946953367608378 10 ..... However, when I try to plot the test-function vs Force I get an error message: plot(test(pressure, 1), pressure = 1 .. 3); Error, (in sol) global 'Force' must be assigned to a numeric value before obtaining a solution

I've been trying to plot the function f:=x->(e^(-a*x^2)-b*x*ln(1+x^2))/(2+x^2+c*sin(Pi*x)); with values a,b,c which have been assigned on maple. when i try to plot the function using: plot(f(x),x=-4..4); I get the error: Warning, unable to evaluate the function to numeric values in the region; see the plotting command's help page to ensure the calling sequence is correct Error, empty plot I have tried all ways i can possibly think and cannot get it to plot the graph. Can anyone help?

Although this question might seem silly to Maple experts, I cannot help asking, since despite a long search through Maple Help and Maple Guides I was not able to come across the answer. What I mean is this: > eq1 := diff(y(t),t)-y(t)^2+y(t)*sin(t)-cos(t) = 0; > # here I want some command that would return the order of eq1, i.e. 1 > something(eq1); > eq2 := diff(y(t),`$`(t,2)) = y(t)*u(t) + diff(u(t),t); > something(eq2,y); # this should return 2 > something(eq2,u); # this should return 1 Besides, I would also need the same for recurrent (shift) equations, i.e.

So what is the best way to put a "link" from one place in a maple document to another. So that someone can jump quickly when clicked? Thanks!

I got an interesting error message

assume(x>0);
assume(lambda>=0);

f:=(x,lambda)->2/(1+lambda)*1/( 1/(x+lambda)+1/(1+lambda));

                                 2                   
(x, lambda) -> --------------------------------------
                            /    1            1     \
               (1 + lambda) |---------- + ----------|
                            \x + lambda   1 + lambda/

ftilde:=(x,lambda)->1/2*(x+1-(x-1)^2*f(0,lambda)/f(x,lambda));

                                2             
               1     1   (x - 1)  f(0, lambda)
(x, lambda) -> - x + - - ---------------------

Hi, I'm trying to solve a set of simultaneous equations, and the solutions I get are expressions of _Z. I'd be most grateful if anyone could explain what this means.

Hi, I stored the closed-form symbolic result of a long computation in a library. When I try to substitute numerical values into the functions I saved, subs (applyrule, etc.) do not make the substitution. Looking at the operand that I think should substitute ('Ip' as stored), it is not evalb equal to 'Ip' (as typed into evalb). It appears that Maple thinks I have two different symbols with the same name. Can anyone explain this behavior to me? Thanks, Art

when you take the limit as x approaches infinity of the following problem Maple 11 give an answer of 1. I think this is not correct. doing the limit manually I get e^ab. Lim (1+[a/x])^(bx) x->infinity I enter the limit using the expression palette. Any input would be welcomed. Thank you.