thank you, ((2^32x)| 128!:3) is the verb that will match standard crc32
----- Original Message ----- From: Raul Miller <[email protected]> To: Programming forum <[email protected]> Cc: Sent: Thursday, April 16, 2015 10:02 AM Subject: Re: [Jprogramming] 128!:3 It's probably worthwhile starting from a "known" starting point. So I selected CRC32 (which pre-filled a lot of fields), and gave it the text: The quick brown fox jumps over the lazy dog "Calculate" with that setup gave me the result 414FA339. This matches http://rosettacode.org/wiki/CRC#J So I would assume that the underlying implementations match. Reading out the tweakable settings for this case, I see: CRC Order: 32 CRC Polynom: 4C11DB7 Initial value: FFFFFFFF (checked) direct Final XOR value: FFFFFFFF (checked) reverse data bytes (checked) reverse CRC result before Final XOR I hope this helps, -- Raul On Thu, Apr 16, 2015 at 9:50 AM, 'Pascal Jasmin' via Programming <[email protected]> wrote: > for say this calculator, > http://www.bobtech.ro/tutoriale/porturi-si-interfete/51-crc-calculator > > what x value will provide the same result to the result box, for data > sequence '123456789'? > > The values that I am trying (which don't match): > > CRC order 32 > > CRC polynom 4C11DB7 > > Initial value FFFFFFFF > > Final XOR value FFFFFFFF (or 0) > > hfd (16b04c11db7;_1)&(128!:3) '123456789' > c4f2be9 > > > > > > ----- Original Message ----- > From: Raul Miller <[email protected]> > To: Programming forum <[email protected]> > Cc: > Sent: Thursday, April 16, 2015 2:49 AM > Subject: Re: [Jprogramming] 128!:3 > > What do you mean by "not match"? > > (Specifically.) > > Thanks, > > -- > Raul > > On Wed, Apr 15, 2015 at 11:34 PM, 'Pascal Jasmin' via Programming > <[email protected]> wrote: >> that helped, >> >> 128!:3 can do any of the functions here: >> >> http://en.wikipedia.org/wiki/Polynomial_representations_of_cyclic_redundancy_checks >> >> >> The default x value >> >> hfd _306674912 >> edb88320 >> >> >> and is "reverse crc-32" >> >> 16b04c11db7 is "normal crc 32" >> >> This does not seem to match online crc 32 calculators though. >> >> >> ----- Original Message ----- >> From: Raul Miller <[email protected]> >> To: Programming forum <[email protected]> >> Cc: >> Sent: Wednesday, April 15, 2015 6:19 PM >> Subject: Re: [Jprogramming] 128!:3 >> >> 128!:3 has width=32 and init=16ffffffff >> >> Here's the CRC32 checksum (which has poly 0x04c11db7) using 128!:3: >> >> (#.|.(32#:2)#:016b04c11db7)&(128!:3) >> >> That said,, I don't see any examples (starting text, ending checksum) >> so it would be tedious to determine whether the default 128!:3 >> polynomial has an exact equivalence. >> >> Thanks, >> >> -- >> Raul >> >> On Wed, Apr 15, 2015 at 5:28 PM, 'Pascal Jasmin' via Programming >> <[email protected]> wrote: >>> is there a named algorithm equivalence of 128!:3 to one in this list ? >>> >>> >>> http://reveng.sourceforge.net/crc-catalogue/all.htm >>> >>> I understand its crc32, but there are several. >>> >>> Also I note that to get the documentation's result I need to take the 2s >>> complement >>> >>> ]&.(2&#. inv) 128!:3 'assiduously avoid any and all asinine alliterations' >>> 1439575093 >>> >>> (j8.02 64 and j6.01 32) >>> ---------------------------------------------------------------------- >>> For information about J forums see http://www.jsoftware.com/forums.htm > >> >> ---------------------------------------------------------------------- >> For information about J forums see http://www.jsoftware.com/forums.htm >> ---------------------------------------------------------------------- >> For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
