MATLAB: Undefined function ‘Trapzoid’ for input arguments of type ‘double’.

Question

Hi, i keep getting this error:

Undefined function 'Trapzoid' for input arguments of type 'double'.

below are my codes:

function [output]=Trapzoid(a,b)
logN=1:8
N=zeros(1,8);
A=zeros(1,8);
for j=1:8
    N(j)=10^(logN(j));
    h=1/N(j);
    x=a:h:b;
    for i=1:N(j)+1 y(i)=exp(x(i));
    end
    for i=1:N(j)
        A(j)=A(j)+0.5*h*(y(i)+y(i+1));
    end
B(j)=log(abs(exp(1)-1-A(j)));
end

whenever i call for function Trapzoid(a,b) for eg, trapzoid(1,8) i will get the error: Undefined function 'Trapzoid' for input arguments of type 'double'. can anyone kindly advise on what actually went wrong? Much Thanks in advance!

Answer 1

Note:

x = a:h:b;
for i=1:N(j)+1
  y(i)=exp(x(i));
end

is less efficient than:

y = exp(a:h:b);