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Jul
27
accepted Logarithmic slider
Jul
12
asked Logarithmic slider
Jul
9
comment Reshape vectors exactly like in MATLAB
@MatthiasOdisio ArrayReshape does the same operation as MATLAB's reshape (and thus it's an $O(1)$ operation). The reason why the results still differ up to a transposition is that MATLAB stores matrices column-by-column while Mma stores them row-by-row.
Jul
9
revised Disable and Enable Hyperlinks Graphics
edited tags
Jul
9
comment Reshape vectors exactly like in MATLAB
That's because MATLAB stores matrix elements in column major order while Mathematica stores them in row major order. "Reshaping" is reinterpreting the stored data without changing it, thus the storage scheme matters
Jul
9
comment Graph rendering not working as expected
I wouldn't call this a bug. Edges are only rendered once, and it shouldn't be of concern how many times the edge rendering function is evaluated. You should construct the edge rendering function so it has no side effects, and the number of times it's evaluated has no effect on the result.
Jul
8
comment DownValues for Built-in Functions
@Leonid So the fact that no DownValues (or other definitions) are visible does not necessarily mean that the function is not fully implemented in Mathematica then? I was never sure about this point. (Not that it makes much practical difference for me.)
Jul
8
comment Lossless TIFF or PNG export
@SqrtOfBlue I'm not sure how to change the colour scheme though. You could transform each value in the matrix to an RGB-triplet manually before applying Image. (There's probably a better way, but this approach would take me less time than looking up the better way :)
Jul
8
comment Lossless TIFF or PNG export
You could create an Image from the data and export that instead. Image exports at 1-to-1 pixel size.
Jul
3
comment Paging RAM in case of memory shortage issue
@Jacob The difference is that with DumpSave you save the definitions associated with a symbol. When you load the file, the symbol and its definitions are simply recreated (and you have to remember what the name of the symbol was). If you use Export, you export only some data (an expression), without associating it with a symbol. When you Import it, Import returns the data itself.
Jul
3
comment Paging RAM in case of memory shortage issue
You can use Export to write (fast to read) MX files. It is often more convenient than DumpSave for data (not code).
Jul
3
comment Paging RAM in case of memory shortage issue
Take a look here instead.
Jul
3
comment Paging RAM in case of memory shortage issue
I'm not sure this would make sense for a program like Mathematica. Yes, programs like Photoshop do this separately from the OS. But for Photoshop it makes sense: it can put the undo history in a file on disk because it does not need to access this information often. Unlike Photoshop, Mathematica is a programming language and the system can't predict what's going to be used and what isn't any better than the OS can. I think you're looking for a solution to not enough memory in the wrong place.
Jul
3
comment How to calculate the whole run time in a specific notebook?
You can have t = AbsoluteTime[] at the beginning and AbsoluteTime[] - t at the end. Or do you need timings for each cell separately?
Jul
1
awarded  Popular Question
Jun
26
revised How to fix MIDI playback on OS X?
added 37 characters in body
Jun
26
comment How to fix MIDI playback on OS X?
Some of this was already explained by Arnoud, but I ran into the problem again, so I thought it would be good to put the solution into its own QA.
Jun
26
asked How to fix MIDI playback on OS X?
Jun
26
answered How to fix MIDI playback on OS X?
Jun
26
comment How to switch off messages on all kernels?
@cesm To use Sjoerd's solution, you need to evaluate the Off[...] in each kernel separately, i.e. do ParallelEvaluate[Off[...]]. Don't forget to turn it back on if it might be useful! (I'd feel safer with using Quiet)