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Topic: Double Integral
Replies: 1   Last Post: Feb 14, 2013 10:27 AM

 Steven Lord Posts: 18,038 Registered: 12/7/04
Re: Double Integral
Posted: Feb 14, 2013 10:27 AM

"Olubode Adetuni" <bodetunji2200@yahoo.com> wrote in message
news:kfgoib\$k8b\$1@newscl01ah.mathworks.com...
> This is a test of my account. I have question on double integral using
> trapz. What is it accuracy particularly for functions like
> y_den=@(x,y)((1+x).^2.*x.^(-11/3).*exp(-(12.*(y.^(2/3)+(1-y).^(2/3)-1).*sig))./(B_bar.*rho_l.*epsilon(u).^(2/3).*d(t).^(5/3).*x.^(11/3)))
>
> x=[0.015:.1:1];
> y=y_num(x);
> area = trapz(x,y);

TRAPZ is just the trapezoidal rule.

http://en.wikipedia.org/wiki/Trapezoidal_rule

If you want to use something more sophisticated, look at INTEGRAL.

http://www.mathworks.com/help/matlab/ref/integral.html

--
Steve Lord
slord@mathworks.com