Convert array of digits to a binary number

Question

How could I convert array of digits to a binary number? For instance:

a=[1 0 1 0 1 0]

I would like to convert to a binary number

b=101010

Is it possible to do without loops?

Instead of using a string-representation to do whatever you want to do, you might want to check the functions bitget, bitset and the ones mentioned there under see also. I haven't seen a case yet, where working with the string-representation is really necessary, nevertheless people ask things like this all the time. Plus, working with strings is slower and eats more memory. — sebastian
– sebastian, Commented Oct 29, 2013 at 16:58

Luis Mendo · Accepted Answer · 2013-10-29 15:26:23Z

19

Maybe this is what you want:

char(a+'0')

Example:

>> a=[1 0 1 0 1 0]

a =

     1     0     1     0     1     0

>> char(a+'0')

ans =

101010

This works by converting each number to its ASCII code (+'0') and then converting the vector of resulting numbers to a string (char()).

answered Oct 29, 2013 at 15:21

Luis Mendo

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3 Comments

To avoid to depend on the peculiarities of ASCII, an alternative would be bindig = '01'; bindig(a + 1).

And if speed is a concern, char(a+48) might be faster. (twice as fast in Octave)

@rayryeng Thanks! That +'0' thing (and -'0' for the way back) is yet another thing I learned in SO :-)

Dan · Accepted Answer · 2013-10-29 15:46:43Z

7

You can convert it to a string:

sprintf('%d',a)

which I think is the only alternative to an array of logicals.

answered Oct 29, 2013 at 15:19

Dan

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Nice, but not the best alternative :)

@DanielR it's an overkill compared to char.