## Physical size of a plot...

How do I change the size of a plot programmatically from the default size? I can do it by clicking the plot and pulling the borders with the mouse, but not programmatically. When using an embedded plot, one can easily define the the size of the plot component in the x- and y-direction (pixelheight, pixelwidth) using SetProperty from the DocumentTools package. I would like to do the same thing for a regular Maple plot, but have been unable to find the right command. Is it possible to do that? Thank you for the help. Peter

## Error, (in pdsolve/numeric) unable to handle ellip...

1. I have a third order PDE with boundary conditions. I try and solve numerically but Maple 9 returns the above error ... Error, (in pdsolve/numeric) unable to handle elliptic PDEs. Would anyone be able to help? 2. If I transform this PDE into an ODE, it returns that there is a "removable singularity at x=0". How do I solve knowing this? Many thanks for any help. Sandra

## How important are calculators?...

Of those of you who use calculators in your daily lives, how many use algebraic and how many use RPN? Do you care which you use, i.e., do you choose algebraic over RPN or vice versa, or is it simply a case of what you grew up with or what an employer expects/requires? Are you in industry or education? Do you imagine that there would be a value to having Maple run on a hendheld device, one with a decent interface and good graphical display? Rich

## 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 ?

## Need help fitting an equation to data......

I'm trying to fit an equation to some experimental data but I'm not sure how to do it. Could someone here please offer their help? I would really appreciate it. I have three fitting parameters: kT, kU, and A. I will post my worksheet below and I will also attach the part where I begin to try to fit the data in case it doesnt read well when I post it here. > restart > ptotal := 0.0000022 ptotal := 0.0000022 > Ci0 := 1 Ci0 := 1 > d 2 2

## Plotting DE Question...

Hey All, I'm new here, but I'm getting a math degree in 20 days if I can finish this project, so hopefully when finals are over I'll be able to stick around. I'm also new to Maple. I have two ODEs which I can plot. I simplified them to be, well, very simple. The ones I want to use are more complicated by a wee bit. de:={diff(x(t),t)=x(t)+y(t),diff(y(t),t)=x(t)+y(t)}; ic:=[[x(0)=1,y(0)=1]]; ic := [[x(0) = 1, y(0) = 1]] Now I want to see how x(t) varies with (t), but all I can find to do is DEplot(de,{x(t),y(t)}, t=0..10, ic);

Hi everyone, I'm new here and I need some serious help. This may seems stupid to you but here it goes. A friend of mine has Maple 10 and I've done my homework with him. But At my school, they've got Maple 6 or something like that and my teacher is unable to see the worksheet that I've done.... Can you help me???

## color the background for text in a plot...

i want to label something in a PLOT structure with TEXT. the problems are that the POLYGON i want to label is (usually) dark. One might solve this by guesstimating the size of the label and putting a white polygon behind it. The problem with this is that text doesn't scale in the same way that polygons do, so when you enlarge or reduce the graph the "text box" no longer holds the text. is there an option for TEXT that will write the label on white? or some other way of doing this? also the text is of variable length (edge weights for a graph, actually). thank you for your help

## number of solutions...

Hi, I need to find how many solutions were found by solve or fsolve. I have solutions := fsolve(eqution,t) and I need to operate solutions in the loop, I have tried to make condition solution[i] <> NULL. It seems to work, but it print an error message(when i is higher then no of solutions). Is there any possibility, how to get no of solutions to bypass that, or any better solution? Thanks for your answer

## How to plot a vertical straight line?...

Hi, this is a really simple question but I just can't seem to find a solution, how do I plot a vertical line in maple such as x=10, everytime I try something it always plots the line y=10 and gives me a horizontal line. Thanks.

## How do I find the period of periodic continued fra...

Finding the period is simple enough, but gets really irritating once the number of terms in the continued fraction expansion gets large. I've scoured the help files and cannot find anything on it. All I have managed to do is right click on the output and convert it to a list. But then I don't know what the command is to find the number of elements in that list.

## Problem in Solving Non-linear PDE...

I am not able to numerically solve a non-linear PDE using "pdsolve". The problem seem to be arising due to non-linearity in the PDE. Once I remove the non-linearity (by removing a partial derivative in X below), the error goes away. The code and the error are included below: X:= Q(t,r)/(Q(t,r)+(0.75*diff(Q(t,r),r))); PDE:=diff(Q(t,r),t)+X*(diff(Q(t,r),r)*1.5*(0.03-r))+Q(t,r)*r=0; IBC:={Q(1,r)=0.01*r,Q(t,1)=10*(exp(1-t)-0.999),Q(t,0)=(exp(1-t)-1)}; ANS:=pdsolve(PDE,IBC,numeric,time=t,range=0..1,method=Box); Error, (in pdsolve/numeric/process_PDEs) selecting function must return true or false