Create a for loop for a function

I want to create a function for volume of the cylinder but it always says 'Undefined function'

function Volume(pi,r)
for r=1:N
    A=r^2*pi;
    disp([num2str(pi) '*' num2str(r^2) '=' num2str(A)])
end
volume(pi,4)

Answer 1

[Joe Yeh]

MATLAB is case sensitive. Your function call should match exactly your function definition.

Answer 2

[Yunus Tunc]

That's why I want to see what wrongs I have