## Maplets -...

Hello, I've got the following problem: I want to build a Maplet with the Maplet Builder. This Maplet shall contain a plot, a slider and a textfield. After moving the slider, the plot shall change and at the same time the textfield shall show the value of the slider. Is it possible to assign two conjunctions to the slider at the 'onchange' field? Thanks for helping, Frauke

## Define function with matrix perhaps?...

I'd like to define a function f(a,b)= product(product(p(a,b,c[i],d[j])^x[ij]*(1-p(a,b,c[i],d[j]))^(1-x[ij]),j=1..n),i=1..n) (The x's are known data, each 0 or 1, the c's and d's are also known.) Is there a way to do this without writing it out long-hand, say using a matrix of the x's and vectors of the c's and d's? Thanks.

## Classic Worksheet Mouse sensitivity problems...

Hello All!
When using Maple 10 Classic Worksheet, the mouse sensitivity goes up tremendously, making it really annoying to work with. The sensitivity is only increased in the Maple window when it's activated. I only have this problem with Classic Worksheet, but it's the 'version' I use. Is there any workaround for this? Like some sort of registry fix?
I'm using a Logitech Mx500, by the way.
Any help is really appreciated!
Cheers

Thanks

## question about fractional form / evaluating cfrac ...

Where can I find a description for the various variants of numtheory:-cfrac, which goes more into details than the online help? For example one can guess how an approximating sum can be obtained from numtheory:-cfrac((a+x)^k, x, 7, 'diag', 'simregular', 'quotients'); but I prefer to cross-check against a confirmed formula instead of guessing. If somebody would be so kind to point me to some source to look at ... or even knows it already ...: how does one evaluate the above list to get a value? -- edited to add: I mean a way which can be compiled and without running through

3 equations are: diff(u_r(r,theta),r)+2/r*u_r(r,theta)+1/r*diff(u_theta(r,theta),theta)+cos(theta)/sin(theta)/r*u_theta(r,theta)=0; -diff(p(r,theta),r)+mu*(diff(u_r(r,theta),r,r)+2/r*diff(u_r(r,theta),r)-2/r^2*u_r(r,theta)+1/r^2*diff(u_r(r,theta),theta,theta)+cos(theta)/sin(theta)/r^2*diff(u_r(r,theta),theta)-2/r^2*diff(u_theta(r,theta),theta)-2*cos(theta)/sin(theta)/r^2*u_theta(r,theta))=0; -1/r*diff(p(r,theta),theta)+mu*(diff(u_theta(r,theta),r,r)+2/r*diff(u_theta(r,theta),r)-1/(r^2*sin(theta)^2)*u_theta(r,theta)+1/r^2*diff(u_theta(r,theta),theta,theta)+cos(theta)/sin(theta)/r^2*diff(u_theta(r,theta),theta)+2/r^2*diff(u_r(r,theta),theta))=0;

## Is this a bug in Matlab code generation?...

Seems that Maple outputs ".." instead of ":" for Matlab code. Note that I'm using Matlab 6.5, so not sure if version has anything to do with it. Is this a bug? Any help would be greatly appreciated. Thanks. >Matlab Code generated from Maple follows

## Having problem with infinite series...

I tried Maple to find a closed-form expression of the following infinite
series:
F:=sum(r^j/(1-a*z^j),j=1..infinity)
where r and a are probabilities and |z|<1.
It did not work
Then I tried to get a series expansion of F around z=0, i.e:
G:=series(F,z=0);
Got the following error message:
Error, (in series/exp) unable to compute series
However when the upper limit of the summation is changed from infinity to any pre-defined number;
ex: F:=sum(r^j/(1-a*z^j),j=1..100)
Maple was able to derive the series expansion around z=0.
Is there any way to get the series expansion at z=0, when the upper limit of the summation is infinity ?

## system of ode of predator prey models...

hi, i don't know maple at all and i need to figure out how to solve this sytem of equations that model predator prey systems in maple but i get an error when i modify this code > e1 := diff(x(t),t) = k*x(t) - a*x(t)*y(t); > e2 := diff(y(t),t) = -r*y(t) + b*x(t)*y(t); to fit this equation- dx/dt = 2x(1-x/4) - xy dy/dt = -3y + xy x(0) = 1 y(0) = 1 if anyone has time to tell me what i can do to get the equilibrium points, the solution and the table of values for this system, i would be grateful

## Appell Hypergeometric Function F2...

Hi, How can i compute the F2 Appell Hypergeometric Function using Maple? Can i write F2 as a function of the F1 appell function? Thank you. Appell Functions: http://mathworld.wolfram.com/AppellHypergeometricFunction.html

## importing data and manipulating it...

ok, my first question, and as I only started using maple about 1hr ago, its probably rather a simple solution that I've missed. I'll tell you what i'm trying to do, and what I've tried so far. I've run some code which has given a formatted output of a lot of numerical data, in 4 columns (which I may wish to call x,y,T and P if I can). I wish to import this data into maple, so that I can eventually plot contour plots with it of T on a x and y grid, and P on an x and y grid. Having tried to use the readdata command to read the file in, I got a lot of row vectors. However I then couldn't find out how to reference specific values in these vectors to allow me to assign them to variable values, or maybe just directly plot them. I tried using the importmatrix command to see if that gave anything, but that failed entirely.

I currently have some MathMLViewers in my maplet and I don't want them to have vertical scroll bar at all times. Does anyone know how to switch vertical scroll bar off for MathMLViewer? Also, is any way that I can have two windows dispaly at same time so I can change window focus by clicking window? Last question, is it possible to display multiple items in ListBox by using Set("ListBox_Name"('value') = blah, blah, blah); Looking forward for your respond, thank you. Tracy