## Rearranging polynomials...

Is there an automatic command (or maybe it is needed a procedure) to rewrite (n+2 -k) * (n+1-k) as (n+2)*(n+1)k^0- (2n+3)*k^1 + k^2 ? Any suggestion will be very useful. Thanks in advance JJaques.

I am looking for the JavaDoc of com.maplesoft.openmaple.* -- is it available somewhere? It looks like the API allows me to do DAG-based calls to Maple, but parts of that API appear undocumented :-( I am working with some people in Ireland who would prefer to pass Maple DAGs rather than strings, and it sure looks like the API allows it, but it isn't fully documented. Help!

## Just a variable...

Dear all: To point: It is possible to build a variable where I can have control of 4 groups of index around the variable, how i show above. G_INDEX1 G_INDEX2 VARIABLE G_INDEX3 G_INDEX4 I apreciate very much your help. best regards JADO

## Imaginary part that (in theory) shouldn't be there...

Just a short question - I tried isolating U(t) below. The paper I got this from didn't give what U would be, but there shouldn't be an imaginary part - I forget what command/assumptions to use in order to get rid of it. I've attached the rest of my worksheet in case anyone wants to see it - the parameters I used in param1 were given in the paper.

e1 := 30 = (0.19e-1*exp(2.5588*U(t))+0.518e-1*exp(2.6788*U(t)))*U(t);

## graphing a second order differential...

I'm trying to graph this differential f''(x) + x/f(x)=0 where y(0)=y'(1)=0 and x is in the range of (0,1) so far I have > de := diff(y(x),x,x)+x/y(x)=0; > ics := y(0)=0, D(y)(1)=0; > dsolve({de,ics}); / 2 \ | d | x de := |---- y(x)| + ---- = 0 | 2 | y(x) \ dx / ics := y(0) = 0, D(y)(1) = 0 it is not solving. Is there anything I' doing wrong?

## Solving a kinematics problem...

Hi, I want to solve a kinematics problem. I have the following DE: > eq1:=diff(v(t),t)+4.646e-4*v(t)^3-7.13e-3*v(t)^2-0.085*v(t)-2.82: Where v=v(t) is the speed and t the time. My goal is to get the space crossed in a period of time: from t=3.35 to t=4.77 (seconds). Additional info: v(3.35)=14.77 m/s v(4.77)=20.4 m/s I've tried solving this with Maple but I couldn't (I'm a Maple newbie). This is what I tried: 1) I isolate the v and dv terms equation, so that: dt=dv/(-4.646e-4*v^3+7.13e-3*v^2+0.085*v+2.82) 2) Then I integrate that to get the time is function of the speed, t=f(v).

## Maple in education?...

Is there an online forum/discussion board devoted to the use of Maple in mathematics education? The forums I know about (here, usenet groups), seem mostly technical. But I have some education questions I'd like to ask - I just don't know where to ask them. cheers, Alasdair

## Optimizing...

I am trying to optimize a function using NLPSolve. The function is in Matlab and Maple calls the function and optimizes it. The values that I am getting are not correct. The optimal values of the parameters are outside the range tha I specify and the function value is not what should correspond to these optimal values. I have attached both the Maple and Matlab codes herewith. Looking forward to your help. Maple File: restart; Matlab:-evalM("cd 'c:/documents and settings/user/my documents'"); mat2map5 := proc (a, b) local Res, res; Matlab:-setvar("a", a); Matlab:-setvar("b", b);

## Calling Matlab from Maple...

I am trying to call a Matlab function from Maple code. In doing this I am facing the following proble: When I use this statement to identify the matlab directory I get an error messgae "too many input arguments": (Matlab:-evalM)("cd c:/documents and settings/user/my documents") However, it works when I use the following: (Matlab:-evalM)("cd c:/") I would highly appreciate if someone could help me out with this. Thanks

## Where is the problem? Why I cannot pointplot3d?...

Hi Maple's experts: (I am using Maple 10.01+WindowsXP ) Given 2 set of numbers x=[1,2,3] and y=[1,2,3] I generate a third which is the addition of x[i]+y[j], as follows: > restart: > with(ArrayTools): > x:= Array([1,2,3]); > y:= Array([1,2,3]); > zxy:=NULL: > for i from 1 to 3 do for j from 1 to 3 do zxy:= Concatenate(1,zxy,Concatenate(3,Array(x[i]+y[j]),Array(x[i]),Array(y[j]))): end do end do: > print(zxy); #I cannot see the "data" > print(zxy[3]); # I see the third line > with(plots): > pointplot3d[{zxy}]; #I cannot plot HERE..."zxy" contains what I want.

## open and close...

I am a beginner with Maple and want to translate a code, that I wrote in Matlab, to Maple. I am facing very basic problems like how to open a data file, how to manipulate data and to write the results in another data file. I would highly appreciate if someone could send me a sample code that performs these very simple tasks. Thanks

## Hide output in for loop...

Stupid question maybe, but how can you hide output of a for loop? The usual : does not work here... Thanks for your help.