Perfect Square in Matlab

What is the most efficient way to check wether a number is a perfect square or not in matlab. Perfect square are 4,9,16 and so on

Answer 1

[Siraj]

Hi,

It is my understanding that you want to know the easiest way to find whether a number is a perfect square or not.

For this first you can take the square root of the number and then see if the square root is a proper integer or not. We know that any integer when divided by one leaves zero as the remainder, therefore we can use the “modulo” function to find the remainder of the square root when divided by one and if the remainder is zero means that the number is a perfect square.

Refer to the documentation for more on modulo function in MATLAB.

n = 49;
%take the square root
sq_rt = sqrt(n);
% now check if the sq_rt is a proper integer or not
int_or_not = mod(sq_rt,1);
if(int_or_not == 0)
    disp("Prefect Square");
else
    disp("Not a Perfect Square");
end

Prefect Square

Answer 2

[Chunru]

x = (1:20);

mod(sqrt(x), 1) == 0

ans = 1×20 logical array
   1   0   0   1   0   0   0   0   1   0   0   0   0   0   0   1   0   0   0   0

Answer 3

[Karan Kannoujiya]

Hi Zaid,

You can use below code to check for a perfect square-->

%num---> number you want to check
y=sqrt(num);
z=ceil(y);
if(z==y)
    disp('The number is perfect square number');
else
    disp('The number is not a perfect square number');
end

Answer 4

[Shivam Lahoti]

you can check for perfect square by using the following check, however representable number might sparse if n is large enough.

if floor(sqrt(n)).^2 == n