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Speed up the loop operation in R
...Biggest problem and root of ineffectiveness is indexing data.frame, I mean all this lines where you use temp[,].
Try to avoid this as much as possible. I took your function, change indexing and here version_A
dayloop2_A <- function(temp){
res <- numeric(nrow(temp))
for (i in 1:nrow(te...
CSS horizontal centering of a fixed div?
...ood answer, but because it no longer is, and the next-highest answer needs all the help it can get to be seen as the best answer NOW. Quentin: I think it would be a good idea to edit in a comment to that effect in the answer itself - I'd then reverse my down vote.
– Nick Rice
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Why does Python print unicode characters when the default encoding is ASCII?
...ng the encoding scheme currently stored in sys.stdout.encoding. Python actually picks up this setting from the environment it's been initiated from. If it can't find a proper encoding from the environment, only then does it revert to its default, ASCII.
For example, I use a bash shell which encodin...
Memory footprint of Haskell data types
... GHC creates a single instance of these constructors and shares it amongst all uses.
A word is 4 bytes on a 32-bit machine, and 8 bytes on a 64-bit machine.
So e.g.
data Uno = Uno a
data Due = Due a b
an Uno takes 2 words, and a Due takes 3.
The Int type is defined as
data Int = I# Int#
no...
What does tree-ish mean in Git?
...--------------------------------------------------
Identifiers #1-14 are all "commit-ish", because they all lead to commits, but
because commits also point to directory trees, they all ultimately lead to
(sub)directory tree objects, and can therefore also be used as "tree-ish".
#15 can also be us...
List tables in a PostgreSQL schema
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In all schemas:
=> \dt *.*
In a particular schema:
=> \dt public.*
It is possible to use regular expressions with some restrictions
\dt (public|s).(s|t)
List of relations
Schema | Name | Type | Owner
-----...
JSON.parse vs. eval()
... and json.parse just parses JSON whereas eval would leave the door open to all JS expressions.
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Reading GHC Core
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GHC Core is the System FC language into which all Haskell is translated. The (approximate) grammar for Core is given by:
Core is closely related to the simpler and better known System F. All transformations GHC does on the Core level are type-preserving refactorings o...
How to get rspec-2 to give the full trace associated with a test failure?
...backtrace (that includes stuff like rails and rspec and other gems) almost all of the time - the only time you ever need it is to debug or understand something caused by the gem itself. So stick to the default backtrace clean patterns, and use -b in the odd case when you need it.
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Access-Control-Allow-Origin wildcard subdomains, ports and protocols
I'm trying to enable CORS for all subdomains, ports and protocol.
11 Answers
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