This is a fairly simple question but my Matlab knowledge is still very limited.

I want to take a given binary number (or rather, a bistring) of length $mn$ and generate an $m \times n$ matrix whose entries correspond to the bit values.

For example, if the given bitstring is $b = 1001110101$ (which is the binary value of the base-10 number 629), and since $b$ has length 10 which can be represented as 2*5, I am looking for a sequence of Matlab commands to convert $b$ to this matrix $A$:

$$ A = \begin{pmatrix} 1 & 0 & 0 & 1 & 1 \\ 1 & 0 & 1 & 0 & 1 \end{pmatrix}.$$

I have come close in the past using cell and string commands, but I never actually seem to get the matrix in the proper sense that I can compute things like $AA'$.

In case it helps, my application program will always generate bitstrings that are of a given length $b = mn$. That is, $m$ and $n$ are known so there is no guesswork when it comes to the size of the desired matrix.


1 Answer 1


There is a MATLAB function in the Communications Toolbox called de2bi that will convert a decimal number to a binary vector. Once you get the binary vector, you can reshape it. The reshape command preserves columnwise ordering, so you might need to transpose the dimensions (i.e., generate an $n$ by $m$ matrix) and then transpose the resulting reshaped matrix (via transpose) operator.

If you don't have the Communications Toolbox, you could probably emulate de2bi using built-in commands. If x is your decimal number, then b = num2str(dec2bin(x.))-'0' will probably work, following this MathWorks Central post. (I haven't tested this function, however, because I don't have a personal MATLAB license.)


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.