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comment Why does this Graphics3D example change lighting on reorient?
It's a beta product, and as such I think some problems are to be expected. I don't quite believe that this is something that we can work around. If anyone can answer it, it would be Wolfram's support.
2d
comment How to parallelize a Do loop containing URLFetchAsynchronous?
I see that you put a bounty on this question, but I feel that you would get better answers with a new question that clearly describes your situation and asks how you can download all the images, based on your conditions, as quickly as possible.
Jul
27
revised Help with PatternSequence
added 2 characters in body
Jul
27
comment Accessing the elements of a list of values
I cannot reproduce the issue you say that you have. Can you post a small working example? You could also use ChebyChase[n_, p_] := lyle[[n+1]] /. x -> p instead.
Jul
27
revised Help with PatternSequence
deleted 82 characters in body
Jul
27
comment Help with PatternSequence
@Guesswhoitis. Jens showed how to do that, the reason I used Replace instead is because it only works on the top level so I don't have to do the Hold/ReleaseHold trick.
Jul
27
revised Generating a large table of values and selecting some of them following some condition
added 70 characters in body
Jul
27
answered Help with PatternSequence
Jul
26
revised Drawing a trihexagonal tiling
added 184 characters in body
Jul
26
comment GDP Per Capita isn't right when called from CountryData?
You can see some of the sources that CountryData uses here. Beyond this we do not know where that number comes from. If you need this data for something serious, then you should use your own source so you know how old it is and any other limitations.
Jul
26
revised GDP Per Capita isn't right when called from CountryData?
added 45 characters in body; edited tags
Jul
25
comment A possible bug about WordCharacter on CJK characters
Your example does not violate what the documentation states, it's just that the reverse isn't true (it would seem): WordCharacter does not not match any character which neither LetterQ nor DigitQ matches.
Jul
24
awarded  Excavator
Jul
24
revised BUG: AssociationMap loses definition
added 32 characters in body
Jul
24
comment How to parallelize a Do loop containing URLFetchAsynchronous?
@M.R. You don't tell URLFetchAsynchronous to use a specific number of threads. Each time you call URLFetchAsynchronous you start a new job in the background. (There may be limits on how many background jobs that can run at once, I don't know what it is.) These functions are rather low level, I'm not sure what a function that loads images conditionally would look like?! Anyway, I would propose to first use URLFetchAsynchronous to get all the HTML that you require for your tests, then based on that create a list of images you want to download. Then use URLSaveAs.. or URLFetchAs..
Jul
24
comment How to parallelize a Do loop containing URLFetchAsynchronous?
@M.R. You won't need to use several cores because that's not what's taking up time. You're not doing any heavy processing. The reason your code without any parallelizing is slow is because you fetch images synchronously; you start downloading one image, and when that's done you start on the next. All your time is spent waiting for the files to transfer, not waiting for your kernels to do computations. Now what if you could download ten images simultaneously on one kernel? That's what asynchronous fetching does.
Jul
24
comment How to parallelize a Do loop containing URLFetchAsynchronous?
To fetch images in parallel from an online source you should use URLFetchAsynchronous and friends. Parallel* functions are not the right way to do it, because you'll spend most of your time just waiting for the server to respond/file transfer. I use URLFetchAsynchronous here.
Jul
24
comment How to parallelize a Do loop containing URLFetchAsynchronous?
It isn't going to work; you have to Sow in the master kernel, like this.
Jul
23
comment Convert a list of lists of rules to a list of values
I was hoping you would include them in your answer, +1.
Jul
23
comment Convert a list of lists of rules to a list of values
myList[[All,1,2]], Last @@@ myList and myList /. {Rule[_,v_]} :> v are all preferable.