q3.mw
Hi!

I have a problem:

Graph a (in blue) and graph c (in red) are plotted, the value of ax,ay and cx, cy are in list.

program as follows:(also in file q3.mw)

with(plots); ax := [13300, 17400, 12500, 20300, 12100, 22100, 11800, 23100, 11600, 23800, 11400, 24300, 11300, 24700, 11200, 25100]; ay := [.2, .2, .3, .3, .4, .4, .5, .5, .6, .6, .7, .7, .8, .8, .9, .9]; cx := [17700,...

 Have to solve and ODE in the domain of [-infnity +infinity ] via specific analytical method but due to some restrictions it could not be solved. In order to solve it, I have separated the domain into [-infinity 0 ] and [0 infinity]. So, I have to add some boundary values at x=0 to the problem. Assuming the solution of the mentioned ODE in  [-infinity 0 ] is g(x) and in [0 infinity]  is f(x), I added the boundary values of f(0)=g(0)=a and f ' (0)=b and obtained f(x...

hi. i sometimes want to see how a subset A of the complex plane behaves under a certain mapping f. i plot A in red and f(A) in blue into the same plot. no problem so far.

but i also want to see how certain points are mapped to better understand the mapping. in some old maple version (like 5) i hacked that in by running through the plot structure and add green lines from z to f(z) for like every 10th entry to the plot.

now in maple...

hi. i am regularly plotting subsets of the complex plane. but i have not figured out yet how i can have the vertical axis labeled with i, 2i, 3i, ... instead of 1, 2, 3, ...

how do i do it?

this error message hapened,but  i try process agin ,this erro disappeared, the proce is perfect, but  then it appear agin. is this a bug?  i use maple 16.

> restart;
> with(plots);
> with(DEtools);
> pendulums := proc (L, angle, velocity, a, b, n) local i, deq, X, Y, inits, slnnf, ACF1, ACF2, ACF3, ACF4; deq := L*(diff(theta(t), `$`(t, 2)))+(diff(X(t), `$`(t, 2)))*cos(theta(t))+(diff(Y(t), `$`(t, 2))+9.81)*sin(theta(t)) = 0; inits := {theta(0...

I think I have come across with what it looks like a very basic bug using the member function. I get the error message: "Error, cannot determine if this expression is true or false: (3) < 100"  after the execution of the last line to the next code:

>Test:=Array(1..3,[1,2,3]);
>member(3,Test,'l');
>if l<100 then print("yes"); end if;

am I doing something wrong ?? I even checked the type of the variable 'l' and it is indeed an integer...

(1) Does ModuleCopy, when automatically called from Object,  really get the a shallow copy of the object

as the first parameter in its parameter list? See below, which is copied directly from ?object,create. The

ModuleCopy has first argument new::Dollar but ModuleApply only passes its two arguments not three. I

couldn't find a reference to this feature in the docs.

hey

I have wired problems with maple !!!

I run a code twice, I get 2 different answers !!!

I have uploaded the code ! just run it twicw and see the numerical values of alpha and beta at the end ! new_idea_gf.mw

In the final line, my output is in the form of tau-c*z. How do I switch the tau-c*z back to 

zeta, because I want to integrate T with respect to zeta.

Thank you. 

> restart;
> with(plots); 
> U := V(zeta)*exp(I*(k*tau-w*z));
> zeta := tau-c*z; 
> Uz := diff(U, z);
> Utau := diff(U, tau);
> Utautau := diff(Utau, tau);
> P := convert(U, trig);
> 
> A := abs(P)^2;
> B := evalc(A);

When I used Maple to solve 3 constants in 3 integral equations, fsolve cannot give me the numerial solutions. It copied the equations and showed me “fsolve（......）”. But if I change the positions of 2terms in the equations (for example a+b is rewritten as b+a), fsolve can give me the numerical solutions for the 3 constants. 

In most cases, I donot know the right order and it cannot give me the results. So what is the problem?...

I'm using Linearalgebra and suppose I have a 10x10 matrix. I want to find the closest element in each column of the matrix to 100. Any idea how to do it?

Being easy to use is nice, but being easy to learn with is better. Maple’s ease-of-use paradigm, captured in the phrases “Clickable Calculus” and “Clickable Math” provides a syntax-free way to use Maple. The learning curve is flattened. But making Maple easy to use to use badly in the classroom helps neither student nor instructor.

In the mid to late ‘80s,...

I need to find the Killing vectors of a metric.

I initiate the session as

> restart;
> with(DifferentialGeometry); with(Tensor); with(LieAlgebras);
> DGsetup([t, r, z, phi], M);

and enter my metric as

M > g1 := evalDG(-dt &t dt ...);

I do not have an unknown function in my metric but I have two free parameters (e.g. a and b).

I use

M > K1 := KillingVectors(g1, parameters = [a, b]);

hi 

if I have two partition Pi and Pi 'I want to know the decomposition of Pi' 

q2.mw

Hi!

I have a question on result storage of for loop.  The program in attached.

The program is relative complex, it is not necessary to look part 1.

The question is in part 2.

The result I proposed is:

r=([17400,12500],[13900])

but, the real result of r is：

r=table([1.0=[1.0,17400,12500],2.0=[2.0,13900],()=[]])

what should I do to modify the program?