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Functions

Create a list of binary numbers

Terminal - Create a list of binary numbers
echo {0..1}{0..1}{0..1}{0..1}
2009-06-23 17:30:20
User: dennisw
Functions: echo
17
Create a list of binary numbers

If you should happen to find yourself needing some binary numbers, this is a quickie way of doing it. If you need more digits, just add more "{0..1}" sequences for each digit you need. You can assign them to an array, too, and access them by their decimal equivalent for a quickie binary to decimal conversion (for larger values it's probably better to use another method). Note: this works in bash, ksh and zsh. For zsh, though, you'll need to issue a setopt KSH_ARRAYS to make the array zero-based.

binary=({0..1}{0..1}{0..1}{0..1})

echo ${binary[9]}

Alternatives

There are 2 alternatives - vote for the best!

Terminal - Alternatives
function decToBin { echo "ibase=10; obase=2; $1" | bc; }
2009-11-24 22:57:58
User: woxidu
Functions: echo
3

Convert some decimal numbers to binary numbers. You could also build a general base-converter:

function convBase { echo "ibase=$1; obase=$2; $3" | bc; }

then you could write

function decToBun { convBase 10 2 $1; }

Know a better way?

If you can do better, submit your command here.

What others think

Although I can't think of a situation where this command would have helped me, it still gets a thumbs up for being cool :-) . Nice one.

Comment by Alanceil 278 weeks and 1 day ago

Really surprised to see this command. I don't know of its use, but it rocks!

Comment by Bluehive 277 weeks and 6 days ago

Wonderful -- I didn't know I could do things like {1..10}. That'll simplify some of my scripts.

Comment by tremby 277 weeks and 6 days ago

@tremby: Yes, "for i in {1..10}; do", for example, comes in really handy. You can also do letters: "{m..p}" gives "m n o p".

Comment by dennisw 277 weeks and 6 days ago

kewl!

Comment by kamathln 267 weeks ago

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