Search All of the Math Forum:
Views expressed in these public forums are not endorsed by
NCTM or The Math Forum.


Sanaa
Posts:
171
Registered:
3/20/12


Need help with integration please
Posted:
Dec 16, 2012 12:54 PM


Hi, I want to integrate the discrete function a*x_n*(1x_n) from nr to t (take r=0.005) > > where a:0:0.001:4 and n=0,1,2,3,...., and t\in[nr,(n+1) r] I have tried the following % define the vector of colors, to plot the data of reach value of r in % different color color_vec = ['b']; r=0.05; for rho = 0: 0.001:10 % define the number of discrete times in interval [k*r, (k+1)*r] n = 50; % define the number of iterations k = 1,.....,Nit Nit = 150; % define the initial vector which is a vector of size n x0 = 0.3*ones(1,n); % define vectors x_next and x_previous x_next = zeros(1,n); %x_(n+1) x_previous = zeros(1,n); %x_n time = zeros(1,n); % initialize x_previous x_previous = x0; x_next = x_previous; hold on for i = 1:Nit time = linspace(i*r,(i+1)*r,Nit); y_next=rho.*x_previous.*(1x_previous); x_next = x_previous+ cumtrapz(y_next); x_previous = x_next; end end plot(rho,x_next(1),'.', 'Color', char(color_vec)) Now I have only one point in the plot!! I also want to integrate from n*r to t!? Any help please. thanks a lot in advance



