## Stop execution on error...

How do I stop maple from running the rest of the worksheet in case an error occurs in the middle of it? Which command should I use?

More specifically, I have a program in which I input the masses of the particles and then the program will calculate the corresponding parameters of the potential, and will do a lot of other stuff with these parameters. However, it these parameters happen to be complex, the program should simply halt with a warning: "your parameters are complex, cannot continue".

## How can I get the numbers from inequalities and ge...

Hi

I've got a list of inequalities

[x > 5, 10 < x]

and I need to plot the region by

plots[inequal]( [x > 5, 10 < x], x = 4 .. 11, y = 0 .. 1);

but I don't want to specify x-range.

So how can I get the numbers from inequalities and generate something like "x = 5-1 .. 10+1"?

Thx :)

## Evaluating multi-variable integration...

Hi everyone,

In my research project, I needed to evaluate a multi-variable integration. I'm trying to do this in Maple, and seems no matter I use Int or int, it failed to evaluate the integration.

Here's my code:

I'm integrating a joint probability density function which is basically a multiplication of four PDFs of four Gaussian distributions:

` `
`> mu := 0:                                                    ...`

Hello everybody! I have a question that how to show the number of roots of Eqs automatically. Followings are part of my program:

>U:=solve({-2/phi^3*u[0]^2*diff(phi,x)-4/phi^3*w[0]*diff(phi,x)-2*u[0]/phi^3*diff(phi,x)^2, -6/phi^4*u[0]*diff(phi,x)*v[0]+12*v[0]/phi^4*diff(phi,x)^2, -2/phi^3*v[0]*diff(phi,x)+2/phi^3*w[0]*diff(phi,y)},{u[0],v[0],w[0]});

I can obtain three items roots. My question is how can I obtain the number of roots automatically by using the program!

## How do I write a procedure that gives an attribute...

I’ve created a basic model of a two-lane road.

## plotsetup and if statements...

Hello

I have Problem with the Maple command plotsetup, it does not seem to work within an if-statement.

What i would like to do is this:

1. Make a matrix with 0 or 1 as enteries

2. convert this matrix into a list where the 1's are points. (So the Matrix entery Matrix[1][1]:=1 would give the listvector:=[1,1]

3. plot these vectors as graphs and store them with the help of plotsetup

4. changing the matrix and rinse and repet 2,3,4 until satisfied

## How do I switch an unknown which was previously se...

`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);`

## Label for inserted image and equations...

Hello everyone.

an equation or a table can have a label and can be later referred to by using insert->label. Can we do the same for inserted images? Like Figure 1, etc.... A workaround is to insert the image in a 1x1 table and reformat the caption. But I am not sure that's the ultimate solution.

Another related question: can an equation that is just in the 2D math mode that is not meant for execution get a dummy label like (*) or (**) or something like that?

## Maple Program runs too slow...

Based on the title, once again I'll mention that the programm that I have been made by using

Maple14 could not run faster.

The function of Maple should be running effectively compared to others.

Hereby, I'll attach the programm for your further action.

That's all, thank you.

## Ordering of Eigenvalues...

I have a 6x6 matrix that depends on 8 parameters, M(F) (F is an 8-dim array, say...), and I want to compute the eigenvalues of this matrix both at a fixed point F_0 and at some other arbitrary point F'. The problem is that I need to make sure the ordering of the Eigenvalues remains the same at these two points, so that if I'd go continuously from F_0 to F' the eigenvalues would go continuously from Eigenvalues(M(F_0)) to Eigenvalues(M(F')), without any flip in the order of the entries.

## Document block question...

`Hi everyone,`
`While I am getting more and more comfortable with the document mode, I have some questions regarding the document block feature:`
`- What is a document block good for anyway?- Why not have the whole document in one block?- Can one join two document blocks?- when do I "remove the document block"- How can I make sure that say an informational 2-D math expression inside a document block never gets executed?-- Can I still...`

## dsolve for systems of differential equations...

Hi, Could some body help me here, Am trying to use dsolve to solve the following system of equations but I am getting the following error

difS := diff(w(t), t) = nu+delta*z(t)-(1/100)*psi*w(t)*(x(t)+epsilon*y(t))-mu*w(t);

difI := diff(x(t), t) = (1/100)*(1-rho)*psi*w*(x(t)+epsilon*y(t))+PI*y(t)-h[1]*x(t);

difC := diff(y(t), t) = (1/100)*rho*psi*w*(x(t)+epsilon*y(t))+(1-q)*eta*x(t)-h[2]*y(t);

difR := diff(z(t), t) = q*eta*x(t)+beta*y(t)-(mu+delta)*z(t)

## How do i plot with curved boundary...

Here is the problem:

plot3d(y+2 x^(2),x=0..1,y=0..h(x), axes=boxed) and h(x)=1+sin(x)

what should i do to make it work?

Thanks for help~~

## Evaluating analytical partial derivatives...

I want to evaluate - del(psi)/del(x) analytically in MAPLE. I wrote the following lines for the purpose :

deltat := proc (x) options operator, arrow; lambda*x^m end proc

Gr := proc (x) options operator, arrow; g*beta*deltat*x^3/nu^2 end proc

xi := proc (x) options operator, arrow; g*beta*x/c[p] end proc

eta := proc (x) options operator, arrow; (1/4)*y*4^(3/4)*Gr^(1/4)/x end proc

psi := proc (x, y) options operator, arrow; nu*4^(3/4...