## imaginaryunit don't work with restart...

If I add "restart" to a program, then interface(imaginaryunit=j) don't work. Why?

***********************************
restart;
interface(imaginaryunit = j);
j^2;
************************************
The output is j^2  but the output should be -1.

## variable spacestep for numerical solution of pde...

Dear all,
How can I input different spacesteps in numerical solution of PDE (Heat equation) with pdsolve of Maple?

For example, the x range is x=0..L,
and I'd like to solve the PDE with spacestep1=L/100 for x=0..a and spacestep2=L/10 for x=a..L.

Thank you in advance!

## How to generate the whole table of quantiles for a...

Hi,

How to generate the whole table of quantiles for a normal reduced centered N(0,1)?

restart;
Chargement Statistics
X := RandomVariable(Normal(0, 1));
X := _R
Statistics[Quantile](X, 0.1e-1);
-2.32634787404074

## Probability Trees...

Hi,

Does maple have the ability to create probability trees / branch plots? (representing a sample space).  I would like to represent a problem more elegantly while learning how to use the software.  For example, a sample space that can be represented could be a coin toss.

## Solving ODE - shooting method, Runge-Kutta method ...

Hi guys,

I have got serious problem with solving this system of ODE, where psi is equal to 10*sqrt(da) and uB,E,kL,uc are constants:

firstly I have to find missing initial condition using shooting method and calculate cA(z=2) using Runge-Kutta 4th order then. And plot following concentration profile for cA and dA. So far, I have dealt with first diff eq 2nd order dividing by two diff eq of 1st order using mentioned constants so I got these ones:

dy[1]:=y2(z);
dy[2]:=1.000000000*sqrt(y1(z))-6.000000000*y2(z)-10.00000000*y3(z);
dy[3]:=-0.8333333333e-2*sqrt(y1(z))-0.8333333333e-1*y3(z);

I understand I need a condition da(z=0) that I should obtain using shooting method, but I do not know how to do it in spite of I understand it in theoretical way. And same problem I have with RK4th order. Anybody here with a hint, please?

There is my maple file (unfinished version of mine): maple-shoot_RK4.mw

## Inverse Laplace transform...

Why Maple doesn't calculate this and only rewrites it??

with(inttrans);

invlaplace(exp((0.2500000000e-1-2.500000000*sqrt(0.116e-3+.8*p-3.2*10^(-10)/(p+0.2e-4)))*x)/p, p, t);

## How do I solve the error described below under Y...

restart;
with(LinearAlgebra);
help("&x");
`&x` := proc (x, y) options operator, arrow; 2*x+3*y end proc;

`&x`(a, b);

[x[1], y[1]]+[x[2], y[2]];
[x[2] + x[1], y[2] + y[1]]
'&.':=proc(u,v)  eval([u[1]*v[1]-u[2]*v[2]],[u[1]*v[2]+u[2]*v[1]]  end proc:
Error, unable to match delimiters
Typesetting:-mambiguous(Typesetting:-mambiguous(primeampperiod

primeAssignproc(ucommav)  evallpar(u(1)sdotv(1) - u(2)sdotv(2))

comma(u(1)sdotv(2) + u(2)sdotv(1))  end proccolon,

Typesetting:-merror("unable to match delimiters")))
&. ([x[1],y[1]],[x[2],y]]);
Error, unable to match delimiters
Typesetting:-mambiguous(Typesetting:-mambiguous(

ampperiod lpar(x(1)y(1))comma(x(2)commay)rsqbrparsemi,

Typesetting:-merror("unable to match delimiters")))
f := proc (x1, y1, x2, y2) options operator, arrow; x1*x2-y1y2 end proc;
(x1, y1, x2, y2) -> x1 x2 - y1y2
f := proc (x1, y1, x2, y2) options operator, arrow; x1*x2-y1y2, x1*y2+y1*x2 end proc;
(x1, y1, x2, y2) -> x1 x2 - y1y2, x1 y2 + y1 x2

## MapleCloud: The account type or email address or p...

I am on a Mac and unable to login to MapleCloud. I can log in perfectly fine via the website in all browsers. Any solutions for this?

How to simplify

a*b=a*c

to b=c ?

## Rolling two dice ?...

Hi,

I try to simulate the sum of two dice, and display the frequencies of the apparitions (in order 2,3,..12). Is my approach good? can generalize the approch to several dices?

Thanks for your help

Simulation2Dés.mw

## Trapezoidal Rule...

Hi every body:

How can I solve this equation with Trapezoidal Rule in Maple?

u(x) = 1+int(x*t*u(t), t = 0 .. 1)

Tnx..

## why is a procedure changing the input?...

I have a procedure that changes the value of an input variable quite unexpectdly. Can anyone explain why? I have a very simplified example of this below.

restart;
with(LinearAlgebra):
switch := proc (V::Vector)
description "This procedure is supposed to take a Vector V and switch entries 1 and 2";
local W,a,b;
W:= V;
a:= W[1];
b:= W[2];
W[1 ] := b;
W[2] :=a;
W
end proc;

V1:=Vector([1,3,5]);
V2:=switch(V1);
I have omitted the output for brevity's sake but all works well as expected.
However,
V1;

returns V2 not V1. Why is the procedure changing V1?

The problem occurs with matrices but not with lists.

Thanks.

## How do i find a solution to a f non-linear equatio...

Hello there,

for academic purposes I need to solve a pretty complex and substantial non-linear equation system. Here you can have a look at the equations:

kompletter_nachbau_v0.mw

The MAPLE Statement "fsolve" is not working here, though there is no error message. I know, that I can provide a framework for each variable to help fsolve find a solution. But for my usage this is not an appropriate task, since I'd like to do some simulations and variations with the input parameters.

Is there a way, so I can find a solution to my equation system?

It would be possible to make some adjustments to my equations, e.g. reducing the complexity of the equations and increasing the number of equations at the same time, if needed.

I would appreciate any advice!