By the time it shows up as an argument to your subroutine, it's not decimal any more. It's just a "number". In fact, internally, it's either a binary integer, or an IEEE floating point value (except on exotic hardware). There's no decimal there.

Now, if your routine took a string, and then did the "multiply by 10 and add the next digit" trick for the entire string, then you'd be converting "decimal to number to binary".

And yes, this does make a difference. It helps to understand that Perl is not thinking in decimal, especially when it comes to floating point values (the 10 * 0.1 != 1.0 problem).

So, even if you wanna sweep it under the rug, my followup is to help inform others that are reading, so that they can be accurate in their understanding and assistance.

-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

In reply to •Re^4: decimal to binary conversion need help by merlyn
in thread decimal to binary conversion need help by Anonymous Monk

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