matrix form numerical integration

This code does not work

clear;
x = [1.0024 0.264 1.4334 1.46 0.0219 0.1; 
     1.0024 0.264 1.435  1.46 0.0220 0.1; 
     1.0024 0.264 1.4352 1.46 0.0221 0.1; 
     1.0024 0.264 1.4353 1.46 0.0222 0.1; 
     1.0024 0.264 1.4354 1.46 0.0222 0.1; 
     1.0024 0.264 1.4357 1.46 0.0223 0.1]; 
r = x(:,1); Y = x(:,2); q = x(:,3); K=x(:,4); L=x(:,5); c=x(:,6);
t =  0.1:0.1:0.6;
z = trapz(t,normcdf(((log(q./K)+t.*c.^2./2)./(c.*sqrt(t))),0,1));

If I just use one line of records, i.e

z = trapz(t,normcdf(((log(q(1)./K(1))+t.*c(1).^2./2)./(c(1).*sqrt(t))),0,1));

Then it works!!! What I dont understand is how to do this 'trapz' for each line of records in the vector 'x'.

Answer 1

[Thomas]

you are trying to perform trapezoidal numerical integration over a number of different values but the output z is not a vector.. MAybe you need something like this.. where you get a z for each line of input data..

clear;
x = [1.0024 0.264 1.4334 1.46 0.0219 0.1; 
     1.0024 0.264 1.435  1.46 0.0220 0.1; 
     1.0024 0.264 1.4352 1.46 0.0221 0.1; 
     1.0024 0.264 1.4353 1.46 0.0222 0.1; 
     1.0024 0.264 1.4354 1.46 0.0222 0.1; 
     1.0024 0.264 1.4357 1.46 0.0223 0.1]; 
r = x(:,1); Y = x(:,2); q = x(:,3); K=x(:,4); L=x(:,5); c=x(:,6);
t =  0.1:0.1:0.6;

for i=1:length(x)
z(i) = trapz(t,normcdf(((log(q(i)./K(i))+t.*c(i).^2./2)./(c(i).*sqrt(t))),0,1));
end

[john birt]

thank you.