# decimal to binary conversion of recurring decimal numbers in matlab

I have made a function convert fractional part of a decimal number to binary, the code is given below:

function [ ret ] = de2bi_( in, itt )
ret='';
for i=1:itt
in = mod(in,1);
in = in*2;
ret = strcat(ret, (num2str(floor(in))));
end
return;
end


here itt is the number of digits required in binary. But when I pass the value of pi it returns the following value

0010010000111111011010101000100010000101101000110000000000000000000000000000000000000000000000000000


which is obviously wrong. Same is the case for any other recurring rational or irrational decimal number. How to solve this issue.

there is nothing wrong, in matlab as in any programming language $\pi$ is represented by a double precision floating number, i.e. a rational number of the form $N 2^{-k}$ where $N,k$ are integers.