Definite Integrals in for-loop
2 views (last 30 days)
Show older comments
I'm trying to setup up this loop. But before I do that I need to declare the functions:
n_grid = 20; % Size of rid
Ms = [];
Js = [];
Ns = [];
Es = [];
J = linspace(0,1,1000);
kappa = 2.*sinh(2*J)./(cosh(2*J)).^2;
kappam = 2*(tanh(2*J)).^2-1;
z = exp(-2*J);
K1 = int(sqrt(1- kappam.^2 * sin(phi).^2), phi= 0.. pi/2)
% Calculating Energy & Magnetisation as a function of interaction strength
E = -J.*(coth(2*J)).*(1+(2/pi)*kappam.*K1(kappam));
An error for K1 shows as follows:
Undefined function 'K1' for input arguments of type 'char'.
Error in ising (line 12)
K1 := int(sqrt(1- kappam.^2 * sin(phi).^2), phi= 0.. pi/2)
What's wrong with my syntax?
0 Comments
Accepted Answer
Andrei Bobrov
on 9 Sep 2016
Edited: Andrei Bobrov
on 9 Sep 2016
Please try code below
J = linspace(0,1,1000);
kappam = 2*(tanh(2*J)).^2-1;
f = @(phi)sqrt(1- kappam.^2 * sin(phi).^2);
K1 = integral(f,0,pi/2,'ArrayValued',true);
11 Comments
Walter Roberson
on 22 Sep 2016
I had no problems with the software once I had done what I indicated above needed to be done.
You might notice that the code in ising.m is spaced oddly. That is because I copied it directly from the pdf and did not bother to change the spacing.
More Answers (0)
See Also
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!