Hi

Any help will be appreciated

I have a continuous time dynamical system

x in R ( set of real number)

t  a positive real time

and the function f_t(x)=x-t

How can we plot or sketch their behaviour in the phase space and in the extended phase space

Many thanks

Hi

We solve the following ode in the interval (0,Pi):

 diff(u(x),x,x)+u(x)=f(x);

bcs=u(0)=0, u(Pi)=0;

Stating one example of many conditions for such equation to have a
valid solution

Many thanks

Dear all ;

I have a Partial differential equation

restart; with(PDEtools);

pde[2] := (diff(u(x, y), x))*(diff(u(x, y), x, x))+diff(u(x, y), y, y);
    where x and y in the square [0,1]

with boundary condition 

bc[2] := u(0, y) = 0, u(1, y) = 0, u(x, 0) = 0, u(x, 1) = 0;

Is there a simple code to compute the solution

Many thanks for any help

Hi

Let D={ Z=x+I*y,    -Pi*(n+1/2) <= x, y <= Pi*(n+1/2)}  

z belong the boundary of the previous square.

I would like to compute the modul of this function  f (z) =  coth(z) using the usual function  cos(x) cos(y), sinh(x) or cosh(y)  and show that | f(z)|  is less than one

Many thanks for any help

Hi

I would like to extract the Anew matrix from the old matrix A. such that each row from Anew matrix has a square form of old matrix i.e all number from each row in the Anew form a square in my old matrix A ...

Is there any loop to determie  the Anew matrix in general  case

Such that A new

A := Matrix([[1, 2, 3, 4, 5, 6, 7, 8, 9, 10], [11, 12, 13, 14, 15, 16, 17, 18, 19, 20], [21, 22, 23, 24, 25, 26, 27, 28, 29, 30], [31, 32, 33, 34, 35, 36, 37, 38, 39, 40], [41, 42, 43, 44, 45, 46, 47, 48, 49, 50]])

Anew = Matrix([[2, 13, 22, 11], [4, 15, 24, 13], [6, 17, 26, 15], [8, 19, 28, 17], [13, 24, 33, 22], [15, 26, 35, 24], [17, 28, 37, 26], [19, 30, 39, 28], [24, 35, 44, 33], [26, 37, 46, 35], [28, 39, 48, 37]])

Many thanks