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Re: [f-cpu] random number generator



hi,

gaetan@xeberon.net wrote:

hello

Yann Guidon a écrit :

A solution that can be practical is to manage a small
"entropy file" (just like under Linux). It contains
the 2^n numbers, can be exported/imported as text
with VHDL functions, and is read during each simulation
startup. If a test fails, the table is not written back
to the file and we can track where the error is.

how does this idea sound ?
why not i will try something right now
ok.


the sentence "This package cannot be sold or distributed for profit."
is not compatible with "pure GNU" philosophy.
well, it's an *implementation*, and what you do is use it,
through a defined interface. so you can use it as you want as long
as you don't distribute it. You can mention in the source
that you have downloaded this library at this address,
so whoever doesn't have IEEE at home can use it.
ok no problem i will not use it

this is not a "ban", it's simply a matter of "interface"
so there is no licensing trouble. The interface itself
seems ok, but the burden goes to anyone who wants
to use your code, (s)he'll have to download the file separately.
it obviously works only as an interim solution.


btw, i have found a way to use Simili 2.3 under windows :
i'll be able to look at your work but i won't have much resources
(PII 300MHz + 64MB) so i hope that your testbenches don't
require too much CPU time :-)
in fact, the benchmark will be portable : windows/linux/other...
i understand, but the worry is to make
a really efficient benchmark that requires relatively
few patterns to cover most bugs.

For example, MR's mltiplier is a really heavy stuff
that could run tens of hours, while a few minutes
are only available in common cases, and there are
other units to test.

low-entropy data can be used first to check
dumb errors, ie using a very simple polynomial LFSR.
Then the rest (like rounding error behaviour and more
sophisticated stuffs including statistical measures) will
need a high entropy pseudo-random generator.

YG

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