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Base conversions with bc

Terminal - Base conversions with bc
echo "obase=2; 27" | bc -l
2009-03-25 09:54:50
User: polar
Functions: bc echo
Base conversions with bc

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.


There are 5 alternatives - vote for the best!

Terminal - Alternatives

Know a better way?

If you can do better, submit your command here.

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
Comment by camocrazed 249 weeks and 3 days 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
Comment by camocrazed 249 weeks and 2 days ago

Your point of view

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