Timeline for What algorithm do the Compress and Uncompress functions use?
Current License: CC BY-SA 3.0
13 events
| when toggle format | what | by | license | comment | |
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| Nov 10, 2017 at 12:14 | history | edited | J. M.'s missing motivation | CC BY-SA 3.0 | added 6 characters in body |
| Jan 25, 2016 at 9:18 | comment | added | Albert Retey | @MarkAdler: Sorry, I realized that my own comment was not very precise: the second part was meant to only address the part whether Compress is using zlib or LZW ("currently" is now recognized). What gzip internally uses and about the details of LZW I have no idea so cannot comment and am inclined to believe what you say is true (should be easy enough to check by those interested)... | |
| Jan 23, 2016 at 23:21 | comment | added | Mark Adler | I was referring to the comment within the web page linked by the comment. Sorry if it appears as if I impugned MarcoB. As for my comment on the comment in the web page linked by the comment, the two things noted as wrong are forever wrong. They are not time dependent. My second comment may be time dependent, hence my use of "currently". If someone has an example of old Compress[]'ed data, then I can look at what it was using then. | |
| Jan 23, 2016 at 22:14 | comment | added | Albert Retey | @MarkAdler +1 for your answer, but I think it is not the comment of MarcoB which is wrong but the content of what he is quoting. As the source seems to be from 2009 it might even be the case that it was correct back then. Have you checked whether this has changed from older versions? The real shame is that this is not more clearly documented... | |
| Jan 23, 2016 at 17:02 | answer | added | Andy C. | timeline score: 21 | |
| Jan 23, 2016 at 9:43 | vote | accept | Andy C. | ||
| Jan 23, 2016 at 1:07 | comment | added | Mark Adler | Also I found that Compress[] is currently using zlib compression, not LZW. | |
| Jan 23, 2016 at 1:00 | history | tweeted | twitter.com/StackMma/status/690700698632216577 | ||
| Jan 23, 2016 at 0:43 | comment | added | Mark Adler | The comment is incorrect (twice in a single sentence), in that LZW does not use Huffman coding, and that gzip does not use LZW to compress. | |
| Jan 23, 2016 at 0:12 | answer | added | Mark Adler | timeline score: 21 | |
| Jan 23, 2016 at 0:07 | comment | added | MarcoB | The best I could find is: "The Compress function in Mathematica [...] is based on a mix of an LZ-like compression scheme and Huffman coding, called the Lempel-Ziv-Welch (LZW) algorithm; this same algorithm is at the base of the widespread gzip data compression software." (from here). See also these questions as commentary: Compress uses too much memory and Is Compress compatible across version? | |
| Jan 22, 2016 at 23:58 | review | First posts | |||
| Jan 22, 2016 at 23:59 | |||||
| Jan 22, 2016 at 23:48 | history | asked | Andy C. | CC BY-SA 3.0 |