# What is the difference between int and integral.

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Ashwani Kumar MAlviya on 9 May 2020
Commented: Star Strider on 12 Oct 2020
Hello everyone
I want to get explained how to decide wheather use function "int" or "integral".
What is the basic difference between them? will they give same answer for a given function?
Thank you very much in advance.
Ashwani Kumar MAlviya on 9 May 2020
n = length(FC); % Calculates the Number of consistant respondents(Nt)
x = sum(FC == mode(FC)); % Calculates the Number of respondents answered mode
p = 1/17; % Probability of selecting mode(Pi)
mu = n*p;
sigma = sqrt(n.*p.*(1 - p)); % Standerd deviation
if n<= 20
i = 0;
syms i
alfa = double(symsum((factorial(n)/(factorial(i)*factorial(n-i))*(p).^(i)*(1-p).^(n-i)), i, 0, x)); % 0 = constant, 2 = x
% beta1 = symsum((factorial(n)/(factorial(i)*factorial(n-i))*(1-1/17).^(i)*(1/17).^(n-i)), i, 0, n-x);
% power = 1-beta1;
elseif n>20
syms y
f = (-(y-mu)^2)/(2*sigma^2); % 5.05 is 2*sigma^2, & 2.7 = mu
fun = (1/(sigma*2.5))*(exp(f)); % 0.2516 = 1/(sigma*2.5), e = 2.71
a = -inf;
b = x; %x; % number of respondent selected mode
alfa = double(int(fun, a, b));
%%% ^ if I am using integral here, I am getting different answer. what mistake am I making conceptually.

Star Strider on 9 May 2020
The int function integrates symbolic expressions (or does its best, consdidering that not all expressions have analytic integrals).
The integral function is for numeric functions, usually anonymous functions.
The documentation pages for those functions explain them better than I can, so I provided links to them.
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Star Strider on 12 Oct 2020
A. Wunsch —
My pleasure!
(A vote is always appreciated!)