I am always surprised how quickly some people conclude a feature is "senseless".
The .mx file is extremely useful if you need to dump a huge set of data to disk during a calculation and then reuse it later during this calculation. I need to use it all the time, and reading and writing is extremely fast. Unfortunately speed comes with non-portability, which is quite understandable. (By the way, much of Mathematica itself comes as .mx files, probably not so "senseless".)
If you need portability, then use .wdx. It is portable, but not so fast to read. And all this is perfectly documented, and no big surprise.
Am 14.12.2012 08:58, schrieb noomen mechri: > Thanks for your reply! > yes, that's what I had to do ... rerun the whole calculation on M9 which > again took a few hours!! (I know ... not good at optimizing code) > But then what is the purpose of having .mx files to save the workspace > variables for future use ... if they can only be read by the version in > which they have been produced ... it is senseless ... > > > On Tue, Dec 11, 2012 at 9:03 PM, Bob Hanlon <email@example.com> wrote: > >> I've never used an .mx file; however, from the documentation: >> >> "MX files cannot be exchanged between different operating systems or >> versions of Mathematica." >> >> "Mathematica MX files can be created with DumpSave and read with Get." >> >> Did you save the source files from which you did a DumpSave? If so, >> move the source files to v9 and DumpSave new .mx files in v9. >> >> >> Bob Hanlon >> >> >> On Tue, Dec 11, 2012 at 2:24 AM, NBM <firstname.lastname@example.org> wrote: >>> Having written a lot of code on M8, I recently switched to M9 and tried >> to >>> run the code which starts by loading an .mx file written by M8, but M9 >> wouldn't read it saying that it was written on another machine. This is a >> major incompatibility issue between M8 and M9. Fortunately I kept my M8 >> installation, so for now, M9 is useless to me. >>> Please a solution. >>> >> >