hi guys,i have a program when i run it after 3or4 minutes maple give this :

execution stopped:memory allocation failed.please see ?alloc for more detail.

when i ok it then give this :

the kernel has been shut down.further computations cannot be performed.

what do you think ?

thank you very much

Are you in or near Berkeley, California?

Are you experienced with Maplesoft for academics?

Can you train a student to use it with the tutorials and your own knowledge?

This student is located at University of California, Berkeley and needs an immediate hands on private trainer.

He will be taking Calculus 1A next semester and needs to learn to use this program this summer.

He is a student who uses an eye control computer without the use of his hands and needs this

Hi,

I'm using Maple 14 and I'm trying to solve a system of recurrence relations with initial conditions (a Vector Autoregressive model). The system is

const:=Vector[column]([0.009421681, -0.0005441856]):
lagY:=Vector[column]([0.796519372, 0.0179147112]):
lagZ:=Vector[column]([0.133049059, 0.5240695764]):
A:=<<const>|<lagY>|<lagZ>>;

eq1:=y(t) = A[1, 1] + A[1, 2]*y(t - 1) + A[1, 3]*z(t - 1);
eq2:=z(t) = A[2, 1] + A[2, 2]*y(t - 1) + A[2, 3]*z(t - 1);

Hi all

I want to simulate the threshold effect in FM modulation\ demodulation, in theory ,when the carrier to noise ratio (the modulated signal SNR)fall below a certain value ,then the signal to noise ratio(of the demodulated signal will fall dramatically and the signal will not demodulated , click sounds will be heard in the output of demodulator. I have tried first "slope detector" as a demodulator, but the threshold effect didn't appear at all when i decrease...

Hi,

i wrote the following code

restart:
zet:=0.5:
rhop:=3880;
rhobf:=998.2;
cp:=773;
cbf:=4182;

eq1 := diff(u(eta), eta, eta)+0.133762025280e-2/(0.993000000000e-3+0.388362300000e-1*phi(eta)+.530162700000*phi(eta)^2)+(1/(eta-1)+(0.388362300000e-1+1.06032540000*phi(eta))*(diff(phi(eta), eta))/(0.993000000000e-3+0.388362300000e-1*phi(eta)+.530162700000*phi(eta)^2))*(diff(u(eta), eta));
eq2 := diff(T(eta), eta, eta)+(.63267672*((2.66666666666*(-1.1752324*10^6*phi(eta)+4.1744724*10^6))*u(eta)/p2+7.04876575828*(diff(phi(eta), eta))-(1.58058605349*(.597+4.45959*phi(eta)))*(diff(T(eta), eta))/(1-eta)))/(.597+4.45959*phi(eta));
eq3 := diff(phi(eta), eta)-5.00000000000*phi(eta)*(diff(T(eta), eta));
p:=proc(pp2) if not type([pp2],list(numeric)) then return 'procname(_passed)' end if:

res := dsolve({eq1=0,subs(p2=pp2,eq2)=0,eq3=0,u(0)=0,u(1-zet)=0,phi(0)=0.008,T(0)=0,D(T)(0)=1}, numeric);
F0,F1,F2:=op(subs(res,[u(eta),phi(eta),T(eta)]));
res(parameters=[pp2]);
evalf(2/(1-zet^2)*Int((1-eta)*(F1(eta)*rhop+(1-F1(eta))*rhobf)*( F1(eta)*rhop*cp+(1-F1(eta))*rhobf*cbf )/(F1(eta)*rhop+(1-F1(eta))*rhobf)*F0(eta),eta=0..1-zet))-pp2
end proc;

fsolve(p(pp2)=0,pp2=(20000)..(8000000));

it has an error and i cannot find that. would you please help me?

thanks

Hello everyone,

I want to know, how we can plot residual errors of the numerical scheme offered with dsolve command? This plot should show that the errors are in admissible range which indicates that the numerical scheme offers high accuracy.

For example, we have a bvp

dsolve({diff(y(x),x$2)-2*y(x)=0,y(0)=1.2,y(1)=0.9}, numeric,method=bvp[midrich]);

How to plot "Residual Error vs x" in this specific case?

 Thanks

Dear Maple users

I am trying to simulate the distribution of Q-values (Karl Peason) in a Contingency table. In that regard I need to use a two dimensional iteration. It require quite a lot of time to perform the computations. Using the values below, it required 1.3 mio iterations and took about 5 minuttes on my computer. My question is if there are ways I can speed it up? It might be using different commands, which are executed faster, performing computations in the...

i have a list of numeric values like this:

r:=[a,b,c,....]

now i want to calculate the quantity

s:=lambda-r^2

which in turn should give me a list again whose entries are:

[lambda-a^2,lambda-b^2,...]

but just doing

s:=lambda-r^2 doesnt work.

lambda is an arbitrary number

a,b ; a^2, b^2, a*b = b*a

is a presentation

a and b are permutation group

a*b = b*a is relation

i am not sure a^2 or b^2 are generator, i guess they are

so how to find a and b which are permutation group?

is it a,b ; a^2, b^2, a*b = b*a     or      a,b ; a^2=1, b^2=1, a*b = b*a  ?

if a^2, b^2, a*b = b*a , i do not know what is a^2 if a^2 = 1

multiplication = composition = permmul

it is like matrix multiplication that has right or left multiplication

when deal with words

a1*a2*a1^(-1)

it will become a2, how to maintain a1*a2*a1^(-1)

because i expect to do some transformation

permutation matrix
1 1

0 1
become group of permutation

1 1 2

1 2 2

fgen:= convert([1,2,2], disjcyc);

however, first row is not 1,2,3

how to do?

Dear Maple users

In a short Maple program I am dealing with a collection of random samples from a uniform distribution. My problem is that every time I call a procedure creating a sample, I get the exact same one! Every run needs a different seed. How do I get a new 'random' sample? I could probably let Maple create all from scratch calling the Sample command with a two-dimensional range, but this will requre a big memory ...

Here is part of my code:

f

1 2 3 4

3 2 4 1

g

1 2 3 4

2 4 3 1
f := permgroup(4, {[[1, 3, 4]], [[2]]});

g := permgroup(4, {[[1, 2, 4]], [[3]]});

mulperms(f,g);
Error, (in permgroup) generators must represent products of disjoint cycles, but [2] does notError, (in permgroup) generators must represent products of disjoint cycles, but [3] does notError, (in convert/plist) bad index into Array

Hello. I am interested in displaying the content of data structures, which has me using the command interface, to instruct for a wider visibility of these.

However, when I typer and execute the command, it simply does not take effect at the first execution, but it requires for me to re-execute it, in order for it to actually display the proper result.

Any explanation for this? To be more specific, this is what I want to instruct:

Hi, 

     I'm computing some difficult integrals, involving Spherical Harmonics. I've proved that the answer must be a real number, and yet Maple returns a complex number. Also Mathematica returns purely real numbers, so I wonder if there is a bug in Maple. I found if I break the integrand into real and imaginary parts, and add them I get the right answer...usually.  Anyway's here's the code and the proof, I suspect they could be a bug...