And now for something completely different - something I don't know how to do in Maple! [ :-) ].
Given a system of linear inequalities, say like
`{a1>5, a2<100, a1 >< a2}`

,
how do I find sample values (integers in this case) in the solution space? For example, I would be happy with {a1=6,a2=3}.

I'm currently outputting some animations, but I'm not using the animate command - I'm using the command
display([seq(tmp_alpha_plot||kk,kk=1..nt)],insequence=true)
having previously created
tmp_alpha_plot||ii:=display([ plot([seq([r_arr[i],alpha1_arr[i,ii]],i=0..nr)]), plot([seq([r_arr
[i],alpha2_arr[i,ii]],i=0..nr)], color=magenta)]):
What would be useful for diagnostics purposes is to be able to print in the corner of the animation both the timestep/frame currently displayed (I know this is automatic when you use the animate command, and I'll change if I need to), and the actual numerical value of the variables alpha1_arr and alpha2_arr. It would also be useful if I could also show the numerical values of some other variables I'm working with, as they're defined at that time.

Hey I was wondering which of the many Root() commands I would use to obtain an Integer root from a large polynomial for example
```
X^2 - 9
```

would return 3
I will be using it for very large polynomials with big coefficents so if there is a more efficent one then that would be helpfull.
Cheers in advance

I want to calculate the normal derivative with Maple?What's the command?Waiting for your help!

Hi - I want to graph an ode and the following are my commands:
> restart;
> with(plots);
> with(DEtools);
> plot1 := DEplot((diff(y(t), t, t))+6*(diff(y(t), t)) = 80*exp(2*t), {y(t)}, t = -1 .. 1, y = -1 .. 1, [[y(0) = 4], [(D(y))(0) = 3]], linecolor = ([BLUE, GREEN, BLACK]), arrows = MEDIUM);
The error I get is :
Error, (in DEtools/DEplot/CheckInitial) Too few initial conditions: [y(0) = 4]
Can anybody tell me what I'm doing wrong?
Thanks.

Hello,
I wonder if someone could explain why, in the attached file, when I collapse the execution groups connected with the 3 equations the label (2) disappears but not the labels (1) or (3). Is there a workaround for this?
Thank you

View 2292_Label (2) disappears.mw on MapleNet or

Download 2292_Label (2) disappears.mwView file
I have this problem with the sum of a recursive seq:
> restart;
> with(student):
> with(plots):
Warning, the name changecoords has been redefined
> a:=5.5*10^(-3):
> R:=10*10^(-3):
> d:=n-> ((-1)^n)*(R-(a^2)/(R+(-1)^(n-1)*d(n-1))):
> d(0):=R:
> afs:=seq(d(n),n=0..100):
> q:=n->(-1*a*q(n-1)/(R+(-1)^(n-1)*d(n-1))):
> q(0):=a*4*3.14*8.85*10^(-12):
> lad:=seq(q(n),n=0..100):
> sum(q(n)/(sqrt(y^2+(z-d(n))^2))/(4*3.14*8.85*10^(-12)), n=1..100);
Error, (in q) too many levels of recursion
How can I avoid this, is the syntax wrong?
An additional question, if I want to plot the seq's how do I do this? I'm a bit over my head here when it comes to maple knowlegde.

Hi - Its me again. Let me try to explain my question with the following:
y := proc (t) options operator, arrow; a*exp(2*t)+b*t*exp(2*t)+c*t^2*exp(2*t) end proc
solve({3*c = -9, 3*b+12*c = 8, 3*a+6*b+2*c = 4}, {a, b, c})
It would be really cool if there was some way I could take the output from solve (values for constant a, b and c) and automatically assign these values in expression y.
I can manually take these and type out y all over again but I think there's got to be a way that Maple recognizes that, alright, here's a, b and c and I'll just assign their values to a, b and c in expression y.

Hi, how can I stop a procedure of maple a use the global variables create before stop the code?
Thanks
Marco

Hi..
I'm a quite new user of maple, so I've got a question:
I'm trying to solve a ode numeric with maple. I've got a solution, a procedure where I a can get a value of y(x) for any x.. (and also plot the "function")
Additionally I would like to have a procedure which can give me the slope of the graph - y'(x) for any x.
Can anyone help me to solve this problem?
My code so far is:
lignsub:=diff(y(x), x, x) = 0.7904982116e-3*sqrt(1+(diff(y(x), x))^2)/(1+0.1012020000e-2*sqrt(1+(diff(y(x), x))^2))
`løsning` := dsolve({lignsub, y(0) = 0, (D(y))(0) = 0}, type = numeric, output = listprocedure)

Please use replies to this blog post for free-form wish list items for Maple 12. Anything you'd like to see, in any part of Maple, go for it.

Am I having an off day, or does the view option for plots (and 3d plots) not work when one has axes=NONE?
For example, the plots
plot( x^2, x=-1..1, view=[-2..2,-2..2], axes=NONE);
plot( x^2, x=-1..1, view=[-2..2,-2..2], axes=BOXED);
produce completely different plots, with the view parameter being ignored in the first version. Can this be fixed?
It seems a bizarre question, but I was trying to create a bit of space around a 3d plot so that it can be rotated without falling off the edge, and I can't figure out how to do that if I don't want axes.

Hi - I'm trying to collect cos(8t) and sin(8t) in the following equation:
(-64*a*cos(8*t)-64*b*sin(8*t))*exp(6*t)+65*(a*cos(8*t)+b*sin(8*t))*exp(6*t)+81*c*exp(2*t)
but the following command just spits out the same exact thing:
collect(lside, [cos(8*x), sin(8*x)])
Any suggestions would be appreciated.
Thanks.

Hi,
I have a ‘slight’ problem (you will probably recognize it Joe! :-) ).
It concerns the values of Tau, omega in my worksheet (see below). If I set Tau=0.7, omega=0.7*m*Eta everything is rosy, and works fine. If I start tweaking these values (which I have to) things go a bit pair shaped.
I either get an error message after the first call to dsolve (e.g. when tau=0.5, omega=0.7*m*Eta) :
*"Error, (in dsolve/numeric/checksing) ode system has a removable singularity at r=1. Initial data is restricted to {Phi(r) = .20650095602297*diff(Phi(r),r)+.82088920025557e-1*I*diff(Phi(r),r)}"*

I don't know how much interest this has for people on this forum, but I have just discovered (I think) a difference in how M10 and M11 handle differential equations. I just received M11 late last week, and when I tried to run in M11 a worksheet I had developed in M10 I got an error. It had to do with the fact that M10 gave me 2 solutions to a DE, whereas M11 gave me one. The first solution which M10 gave me was r(theta) = 0. M11 skipped this trivial solution. Arguably this is a better way to go, but it can cause problems for older worksheets, as it did on mine, where my next line tried to parse the second solution of the previous line. I have uploaded a file which illustrates this. Is it possible that there is some setting I could change in M11 to make it give me the same set of solutions as M10 gives?