For example, in the list [1,1,1,1,2,4,6,1,9], how many 1s are there?

Is there a procedure in Maple? Or how can I manage to do it?

See the attached worksheet: myDet.mw

Why does the determinant of A  contain  x, x^3, x^5, x^7 and x^9 ?

Maple15/Linux/Fedora16_x86_64

i am solving for a system of df eq's, but the eq's have these little tricky integrals inside them.....so it either retards operation or no solutoin can be found...They look like...

B_12:=(10*a_2*a_3)*(u/( ((10^2+u)^(3/2)) * ((a_2^2+u)^(3/2)) * ((a_3^2+u)) )):

B_122:=(10*a_2*a_3)*(u/( ((10^2+u)^(3/2)) * ((a_2^2+u)^(5/2)) * ((a_3^2+u)) )):

B_123:=(10*a_2*a_3)*(u/( ((10^2+u)^(3/2)) * ((a_2^2+u)^(3/2)) * ((a_3^2+u)^(3/2)) )):

B_23:=(10*a_2*a_3...

My problem looks as follows................pts1FIXED comes from dsolved solution......it plots a empty figure...and i checked that l(the data pairs looks fine)..

--------------------------------------

Energy:=array(1..450);

Time:=array(1..450);

for i from 1 to 450 do 

	

	Energy[i]:=-1*((32*G*Inertia^2*e^2)/(5*c^2))*pts1FIXED(i);

end do:

l := [[t,Energy[t]] $t=1..450]:

plot(l,style=point,symbol=circle,color=blue);

I need some help...i need a solver using the Runge-Kutta method adaptive size control, to solve a sytem of 5 diff eq's, all of them are interlinked...

And 

Say that dsolve numeric produces a results, called Solution, Now ex  solution(0)=1, and in general solution(t) can be evaluated, now, i want to use this, in E(t)=2*solution(t), in a plot, thus...

plot(E(t),t=0..100,....), but returns the error....

hello everyone, this is my first time visit mapleprimes, i just started to use maplets programming, so there are a lot of things i still don't know about this maplet, if i ask some stupid questions please be patient with me.

so i've been trying to write a maplet that will calculate some simple functions such as addition, multiplication, division,...,it's kind of like a calculator. 

i've been trying all day, and no luck so far. help please. 

Ok, I am not a very experienced user, but I am mystified by this.  The essence of the problem is that when entering a range of values in an integration, I get a different answer if the range is given as 0..1 to if it is given as 0.0..1 or 0..1.0. Here is the program

### dgig
dgig := proc(psi, chi, lambda, t)
    (psi/chi)^(lambda/2)*t^(lambda - 1)*exp(-(psi*t+chi/t)/2)/\
    (2*BesselK(lambda,sqrt(chi*psi))):
end: ## End of dgig

if i want to create a table which contain buttons label from 0-9 so when i calculate n! i can use the number buttons on the table? please help. 

Suppose I have a file of text that I would like to read into a Maple (16) worksheet as a string. (I have in mind encrypting the string using the RSA encryption scheme.)

If I paste the text directly into the worksheet and surround it by ",  I have no problem, but if I try to read, for example, a file some_text.txt using a command like

     read("C:\\Users\\MyName\\Desktop\\some_text.txt");

I've created a matrix in which each row has two values. I'm using Add(i,i=[matrixName][row element number])/2 to find the mean of each row, which I'd like to transfer to a corresponding element number in an array or a vector, but so far I can only get it to work on single rows or (if I use only Add(i,i=[matrixName]/2), understandably, the mean of the whole matrix. Is there a way to do it wholesale?

Hi! I need help with my project I dont know where to even start!

Question:

Consider a simple polymer , which consist of long chains of simple molecules attached to each other, e.g:

....-CH₂-CH₂-CH₂-...

If the interaction energy between consecutive sections ca be ignored or is low enough, the chain can be bend around at varios places to form varios configurations. One can start by  fixing the first section...

i found this program in mapleprimes 

Hello! I am trying to graph the following: 

dx/dt = -10*x + 10*y 
dy/dt = r*x - y - x*z 
dz/dt = -(8/3)*z + x*y 

where x, y, and z are all functions of time (t). Solve the equations subject to the constraint that r = 25 and the initial conditions that at t = 0, x = -1, y = -1, and z = 1. 

This is my code:
DE*plot3d({d*x(t)/dt = -10*x(t...

Hi everyone 

Is there a method in maple to plot a rectangular matrix.

Amr