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Where can I learn how to write C code to speed up slow R functions? [closed]
...d Use the source, Luke! --- R itself has plenty of (very efficient) C code one can study, and CRAN has hundreds of packages, some from authors you trust. That provides real, tested examples to study and adapt.
But as Josh suspected, I lean more towards C++ and hence Rcpp. It also has plenty of exa...
Android destroying activities, killing processes
...the user, because another activity has been resumed and is covering this
one. This may happen either because a new activity is being started,
an existing one is being brought in front of this one, or this one is
being destroyed. Followed by either onRestart() if this activity is
coming back ...
How to Correctly Use Lists in R?
...ate the 'switch' statement in C++, Java, etc. in languages that don't have one; probably a good way to do this in R when i need to). +1
– doug
Jan 12 '10 at 23:30
8
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Shortcut to comment out a block of code with sublime text
... In Notepad++ and Geany (for example, amongst others), you have one command to comment AND another, different one to un -comment. That's very useful if you want to select a whole block where some lines are commented and some are not, and put everything under comments, or everything withou...
Is there an MD5 Fixed Point where md5(x) == x?
...
True, if you had to try every one. But you would only have to try every possible input to verify that there was no fixed point. If there is a fixed point (and Adam Rosenfield's answer suggests that there might be) then one lucky guess is all that's needed...
What's the difference between utf8_general_ci and utf8_unicode_ci?
...o equivalent _general variant. People reading this now should probably use one of these newer collations instead of either _unicode or _general. Much of what's written below is not of much interest anymore if you can use one of the newer collations instead.
Key differences
utf8mb4_unicode_ci is bas...
Grouping functions (tapply, by, aggregate) and the *apply family
...h of them, though, that beginning useRs may have difficulty deciding which one is appropriate for their situation or even remembering them all. They may have a general sense that "I should be using an *apply function here", but it can be tough to keep them all straight at first.
Despite the fact (n...
Access restriction on class due to restriction on required library rt.jar?
..."Configure Build Path", "Libraries" (tab), you should see "Add Library" as one of the buttons on the right... This worked a charm for me as well, excellent answer
– Alexei Blue
Jun 14 '12 at 9:57
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C# Lambda expressions: Why should I use them?
...tate to the function without adding parameters to the function or creating one-time-use objects.
Expression trees are a very powerful new feature of C# 3.0 that allow an API to look at the structure of an expression instead of just getting a reference to a method that can be executed. An API just ...
Function vs. Stored Procedure in SQL Server
...ments). Functions are not allowed to change anything, must
have at least one parameter, and they must return a value. Stored
procs do not have to have a parameter, can change database objects,
and do not have to return a value.
...