Sanaa
Posts:
171
Registered:
3/20/12


Re: Integration with variable limits
Posted:
Jul 25, 2013 4:58 PM


"Torsten" wrote in message <ksrcel$2k$1@newscl01ah.mathworks.com>... > "Sanaa" wrote in message <ksrbia$r0l$1@newscl01ah.mathworks.com>... > > Hi all, > > How to integrate a function within a loop and the limits of integration are variables? > > For instance, y(i)*(1y(i)) is the function I wish to integrate from 0.25*i to t where > > t \in (0.25*i, 0.25*(i+1)). > > Any help is really appreciated. > > Sanaa Moussa > > I think y(i)*(1y(i)) is just a real number, not a function, isn't it ? > > Best wishes > Torsten.
Thanks for replying. You are right, but I mean the function is y*(1y) which I want to put it into a loop My code is itermax=300;min=itermax9;% That is we plot from 291:300 i.e. 10 values of x only. r=0.25; for rho=0:0.001:4 %x0=0.1; x(1)=0.1; for i=1:itermax1 %t=linspace(i*r,(i+1)*r,itermax) y(i+1)=x(i); x(i+1)=x(i)+ rho*int(y(i)*(1y(i)),i*r,(i+1)*r); end %fix(y) plot(rho*ones(10),x(min:itermax),'b.','linewidth',0.1) hold on end fsize=15; xlabel('\rho','FontSize',fsize) ylabel('\itx','FontSize',fsize) %title('r=0.25, \alpha=1','FontSize',fsize) hold off % print(gcf, 'djpeg', 'zbuffer', 'bif.png');
I get the error Function 'int' is not defined for values of class 'double'. what does this mean and how to fix it please? Many thanks in advance.

