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visits member for 3 years, 2 months
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Ok, an obligatory note: opinions expressed here are mine and not those of my employer.


2d
comment DatePlus and DayPlus perform much worse than my user-defined-function
Have you seen some of the past questions / answers on this topic, involving Java, like this discussion for instance? I found that for date functions, and when you need to perform operations in a bulk, this approach works well.
2d
comment Ordered associations
Apparently, this seems to not be mentioned in the docs explicitly, at least not on the main Association doc page. One can sort of figure this out by the fact that one can use Part with numerical indices on associations, but such fundamental property should be mentioned explicitly. I will file a suggestion report.
Mar
27
comment Ordered associations
Associations are ordered.
Mar
26
answered Testing a package in Mathematica 9
Mar
24
revised Why can I not replace a Dataset using a rule?
Correction to my last statement
Mar
24
revised Why can I not replace a Dataset using a rule?
Added a note why this method might be better
Mar
24
comment Why can I not replace a Dataset using a rule?
+1. Apparently, more complex solutions are always late.
Mar
24
answered Why can I not replace a Dataset using a rule?
Mar
24
revised How to find out where an error occurs?
Generalized the functionality of debug
Mar
24
answered How to find out where an error occurs?
Mar
24
comment How to find out where an error occurs?
I wrote a function, debug, which implements some of the suggestions given to you in comments. You can try using it, it has been one of the best debugging tools for me. I have also included it in RLink, so you can call Needs["RLink`"], and then call RLink`Developer`debug[your-code].
Mar
24
answered Count elements between matching opening and closing parentheses?
Mar
22
comment Dynamic arrays and lists with compile (Append, Linked lists etc.)
There is also this question
Mar
22
comment Match opening and closing parentheses?
Not to diminish this answer (I upvoted it), but just for future visitors who might not know it: this one will in general have a quadratic complexity in the size of the list with parentheses (which was the main reason I discarded this version myself, when answering).
Mar
21
comment How to convert a notebook to an association and back?
@rcollyer I'd agree with this. The problem of denormalization is more important either when this leads to excessive memory usage (less important issue), or when the database is writeable and the data may become corrupted if it exists in several places and goes out of sync. For read-only databases this is much less critical.
Mar
20
comment Dataset: sort rows in descending order of first column
dataset[SortBy[-#a &]].
Mar
20
answered Match opening and closing parentheses?
Mar
20
comment Resource management in Mathematica
Somehow I missed this answer, and only discovered it by accident when looking at the old SO question on this, and seeing your more recent comment there. I've been using your CleanUp function from that old post extensively, but this seems a better alternative. Big +1.
Mar
19
comment Does Mathematica support out-of-core Associations?
It does not yet, but the support for it mau be added in the future (I am not speaking in any official capacity here, so this is just a guess).
Mar
19
comment Does Mathematica support an unordered set (e.g. hashset) data structure?
I think that for all practical purposes, you can consider Association to have O(1) complexity for all those operations. The point is that, implementing on the top-level any such structure would lead to constant factors far greater that log n for any sensible size of the set. You can also try System`Utilities`HashTable, described in e.g. this answer.