Undefined function or variable error

option=input('Do you want to continue?(Y/N)','s');

while option == Y

%here comes body of loop

option=input('Do you want to continue?(Y/N)','s');

end

it says undefined function or variable input when I enter Y

Answer 1

[Jan]

Replace while option == Y by

while strcmpi(option, 'y')    

In your code Y is a function call, not the character, because the quotes are missing. Using strcmpi accepts lower and upper case characters and compares the string in total, not elementwise as teh == operator. See:

c = 'yy'
c == 'y'  % This compares both characters and replies [true, true]
strcmp(c, 'y')  % This is a scalar as wanted

[Rabbia Sajjad]

It worked. Thank you!

Answer 2

[madhan ravi]

'Y' not Y