23 Sep
2022
23 Sep
'22
8:47 p.m.
On Fri, 23 Sep 2022, Randy Dawson via cctalk wrote:
On the top secret number cruching....
The Cray had an instruction called 'population count'
asked for by the NSA.
The number of bits on in a word, not sure what this was used for.
Interesting.
A friend of my ex was asked to code that (in C) as a test in a job
interview.
It was useful as a simple test of whether an applicant had any
bit-twiddling experience. But, I couldn't think of practical application.
Perhaps, some measures of central tendency of values of that in a large
body of data could be useful for testing randomness in cryptography, such
as checking for steganography?
--
Grumpy Ol' Fred cisin(a)xenosoft.com