## Pi/pi as a positive number...

I have a procedure

smth:=proc(T::positive)

bbbb;

end proc;

When I type

smth(Pi);       or     smth(pi);

I obtain the error message

Error, invalid input: smth expects its 1st argument, T, to be of type positive, but received pi

How can i give the Pi/pi to T  if I want to keep  the T::positive  ?

(evalf is not acceptable.)

Sandor

## Dynamically setting size in matrix questions...

Dear All,

I'm creating matrix questions and wish to dynamically set the size of the matrix. So I'm trying something like this:

\qutext{Find the transpose of the matrix $$A=\left[\begin{array}{ccc} 1 & 2 & 3\\ 0 & 1 & -2\end{array}\right]$$}

\code{$a=3;} \size{$a}{2}

<snip>

But this doesn't seem to work.

Thanks

Colin

## Importing question banks...

Dear All,

Whenever I import a question bank I get the following error:

Error Message:

 Errors loading the question bank, first : Reason: Error at line 0. Stream closed

However, the question bank seems to have imported correctly. Any thoughts?

Thanks

Colin

How do I add a new line in the middle of an existing execution group without using split/join commands in Maple 11.

## op(plot1)...

dustplot0:=(points)->odeplot(duffing, [x(t),y(t)], 0..(2*Pi*points), numpoints=points);
plot1 := dustplot0(100):
plot1;

plot2:=PLOT(POINTS(op(op(1,op(plot1))),COLOUR(RGB, 0, 0.2,0.5),SYMBOL(POINT))):
plot2;
Error, invalid input: op expects 1 or 2 arguments, but received 3

I do not understand the reason for this error.

Thanks

## ODE IVP...

My problem is that Maple does not give answer at all for the initial value problem, so I need a help. If does exist a solution how can I obtain it?

infolevel[dsolve]:=5;
5

## Matlab <---> Maple equivalent commands...

What is the (symbolic) equivalent in Maple for

   [ V  D ] = eig( A, B, 'chol' )


for given matrices A, B ?

## Problems installing Maple11 on Vista, please, help...

Hi!

I was trying to install Maple11 on my computer (Windows Vista Home Premium, 2GB on RAM) but I cannot do it, when I executed maple11windowsinstaler.exe appear this message:  "Installer user inferface mode not suported": Unable to load and to prepare the installer in GUI mode... Why appear?? I need to intall maple as quick as possible. I tried to run the installer with  "run as administrator", but i cannot install.

## can i delay the output?...

Hi, I am just courious and I want to delay the output like: If I ask maple to do an integration, first it displays the question: Int(x,x); then after some time it displays the answer int(x,x); is there a way to do that?

## Axis in degrees...

I'm a teacher and I'm teaching my students about graphing trig functions. Well, they do not know about radians yet and I need to keep everything in degrees and would like to plot my graphs in degrees and show that the graph is in degrees on the axis, but I can't find a way to do this. Can anyone help me with this!

thanks,

Clinton

## converting tan(z) to sum form with assumption...

Hi,

I am trying to convert tan(z) to sum form using the convert(...,Sum) command and using some information from FunctionAdvisor.
The second operand of FunctionAdvisor( sum_form, tan) gives me the domain of validity.
I would like to use this info during the conversion as assumption, but it doesn't work for me.
(Of course, the first operand is the required sum form, I am just playing with maple).
Here is my problem:

## confused about piecewise()/levels of evaluation...

Unfortunately piecewise() is a builtin so I can't see the library code.

I'm trying to construct a sequence of arguments to piecewise() programmatically, and to assign the result to a function but I just can't seem to set it up correctly.

I have a 10x18 matrix, each row of which will be used to define a piecewise linear function, so the columns in a row define the endpoint values of each line segment.

Essentially what I'm trying to do is the following (giving some Maple pseudo-code which doesn't work, but hopefully will get the idea across):

## Definite Double Integral = Definite Integral...

On page 99 of Dr. Euler's Fabulous Formula, Nahin says that:

int(int(f(s), s = 0 .. t), t = 0 .. x) = int(f(s)*(x-s), s = 0 .. x)

is true and I believe it, but I can't get Maple to confirm it.  How can I get Maple to agree with Nahin?  Are there assumptions that will make it happen?

## how do i evaluate in degrees ?...

Hi,

I want to evalute in degrees.

restart:with(Units[Natural]):

sin(45 * deg);  # it works

>alpha[1]:=4.25 * deg;
> theta[1]:=11.31 *deg;
> theta[2]:=78.69 *deg;
> alpha[2]:=-9.25 *deg;
> a:=1400.00;  #  a and b should be real values
> b:=509.90;

>-b*sin(alpha[2]+alpha[1]-beta[1]-theta[2])+b*sin(beta[1]-theta[2]):

Error, (in Units:-Standard:-+) the units arcdeg and 1 have incompatible dimensions

not working...