Hi,

I have been trying, without success, to reproduce the plot consisting of the family of curves for the equation v(t), as can be seen on this web page : http://tutorial.math.lamar.edu/Classes/DE/Linear.aspx.

Any help appreciated.

thanks,
Andrew

Hi all,

I'm currently running a parameter space search via Maple scripting. The pseudo-code goes something like this:

fopen text file to write data to;

initialize parameters (variable) x, y, and z;

for x number of iterations

   A:-Simulate(model.msim, with [parameters]);

   Update parameters with new values;

   Write to text file;

end do;

fclose(text file)

I use Maple 15 and I want to take the real and the imaginary part of a simple expression e.g. 5*Dirac(x)+3*I, having already assumed x a real value. However, Maple seems to have problem with the Dirac function. The output looks like this:

> assume(x, 'real');
> Re(5*Dirac(x)+3*I);
                         5 Re(Dirac(x))
> Im(5*Dirac(x)+3*I);
                       3 + 5 Im(Dirac(x))

Any thoughts on how to overcome this are welcomed.

Hi I'm new to maple and have to solve this:

Find the transferfunction

I beleve the answer should be:
H(s) = Y(s)/G(s)  =  1/(s^2+(1/4)s+1)   (correct me if I'm wrong)
but i have to show how to do it in Maple in a scool project

please help me have tried for several hours now, but cant get it right

restart; with(plots); Eq1 := diff(f(eta), `$`(eta, 3))-(diff(f(eta), eta))^2+m*f(eta)*(diff(f(eta), `$`(eta, 2)))-(M^2+lambda*P)*(diff(f(eta), eta)) = 0; Eq2 := diff(theta(eta), `$`(eta, 2))+m*pr*f(eta)*(diff(theta(eta), eta))-lambda1*pr*theta(eta)*(diff(f(eta), eta)) = 0; bcs1 := f(0) = s, (D(f))(0) = -1, (D(f))(10) = 1; pr := .72; M := 1; m := 2; lambda := 1; lambda1 := 1; bcs2 := theta(10) = 0, theta(0) = 1; L := [0.5e-1, .1, .2, .4, .6, .8, 1, 5, 10, 20]; for k to 10 do R := dsolve...

Hi everyone, I am getting this error message in maple can i get any help

Error, (in DynamicSystems:-RouthTable:-RouthTable) the polynomial must not contain complex values

Hi all

Can anyone suggest ways of speeding up this code ?

div_vec := proc(a::Vector,b::Vector)
  # procedure returns the element-byelement
  # division of vector a by vector b
  local i,c:
  c:=Vector(Dimension(a)):
  for i from 1 to Dimension(a) do
    c[i]:= a[i]/b[i]:
  end do:
  return c:
end proc:

Thanks

LR

Let G be an undirected graph having the vertices V={1,...,n}. A subset {i,j,k} is said to be a triangle of G if the complete graph with these vertices is a subgraph of G.
How to find the number of all triangles of G in an optimal way? The code should work with RandomGraph(400,1000).

Is there a simple way to have Maple re-formulate an expression like:

  r^2 * sum(A(j)*r^(n+j))

to :

  sum(A(j)*r^(n+j+2)

simplity, collect doesn't seem to do it.

Is there a simple function, or does one have to revert to the subsop procesure reported in a 2008 post.

Thanks.

I want maple 15 to show me how it works out the formula (transposition) from N = 40^(1.5t) to t = 0.666..7(ln(1/40)*N)

I want to know how it transposes this formula from N to t I want the steps the actual working, I can't seem to figure it out as I'm using maple 15 as a learning tool, I have all the student modules installed but have no idea what I'm doing here

> N = 40*exp(1.5*t);
                       N = 40 exp(1.5 t)

Hi all,

I wonder if it makes sense to use tables as datatype for efficient maple code. I need this datatype to pass parameters to a procedure which is called many times.

In particular, I have the following criteria:

* efficient (fast) to access for read and write.

* potentially thread save ( I can also imagine having individual copies for each thread)

* present in future Maple versions

* easy to transform into C-code later

I was introduced to the geometric interpretation of correlation and linear regression recently.

Orignially due to the famous statistician R.A.Fisher, the idea is that the correlation between 
two variables is the cosine of the angle between the 2 vectors in n-dimensional space.
This can be demonstrated in Maple as follows:

First, we represent each variable as a vector and transform it so that it is centred at its
mean and has a length equal...

I want to solve equations,program in maple as follows:

solve({n = b+2*c+q+2*r, (a+b+c)/(p+q+r) = 9, n*b-3.32*a*(a+p+2*n)*10^(-7)*t^(5/2)*exp(-18.27*10^4/t) = 0, n*c-3.32*a*(a+p+2*n)*10^(-7)*t^(5/2)*exp(-32.035*10^4/t) = 0, n*q-3.32*p*(a+p+2*n)*10^(-7)*t^(5/2)*exp(-9.16*10^4/t) = 0, n*r-3.32*p*(a+p+2*n)*10^(-7)*t^(5/2)*exp(-18.77*10^4/t) = 0, a+b+c+p+q+r+n-.73*10^28/t = 0}, {a, b, c, n, p, q, r})

I can't get the results but  "Warning, solutions may have been lost"

Can anyone help me write a procedure for Maple 15 that does the following:

INPUT: number of unknowns and equations n; augmented matrix A=[aij], where 1<=i<=n and 1<=j<=n+1.
OUTPUT: solution x[1], x[2], ... , x[n] or message that the linear system has no unique solution.

Step 1: For i=1,...,n-1 do steps 2-4.  # Elimination process.

Step 2: Let p be the smallest integer with i<=p<=n and A[p,i]≠0.
          ...

every time I enter / or ^, maple automatically changed the text I entered into fraction or power, and I am having hard time enter equations normally like the way I do in graphic calculator or matlab. I am forced to type all my equations on a text pad and then copy over.

is there a way to stop maple from auto formatting my input text? I am more of a matlab guy and I really need to use symbolics and integration abilities right now, but this version of maple is making...