Base conversions with bc

echo "obase=2; 27" | bc -l
Easily convert numbers to their representations in different bases. Passing "ibase=16; obase=8; F2A" to bc will convert F2A (3882 in decimal) from Hex to Octal, and so on.
Sample Output
$ echo "obase=2; 27" | bc -l
$ echo "ibase=16; F2A" | bc -l
$ echo "ibase=16; obase=8; F2A" | bc -l

By: polar
2009-03-25 09:54:50

What Others Think

seems to me that this doesn't work all the time: This is correct: echo "ibase=2; obase=4; 01100001"|bc -l 1201 But the following aren't: This one outputs the answer in base 3, not base 16: echo "ibase=2; obase=16; 01100001"|bc -l 10121 This one doesn't do any conversion at all: echo "ibase=2; obase=10; 01100001"|bc -l 1100001 and here's a workaround that seems to do what it should, with the added benefit of being able to supply the number on stdin: echo "obase=16;$(echo "ibase=2;$(head -n 1)"|bc)"|bc
camocrazed · 602 weeks and 1 day ago
I stand corrected. Setting the ibase changes it for all the following numbers, including the one supplied to obase, but only for multi-digit numbers. A better workaround to this than my previous one is to simply put obase first "obase=16; ibase=2; 01100001"|bc -l 61
camocrazed · 602 weeks ago
seofox · 9 weeks and 5 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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