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Fastest way to find second (third…) highest/lowest value in vector or column
... min lq mean median uq max neval
Rfast 160.364 179.607 202.8024 194.575 210.1830 351.517 100
maxN 396.419 423.360 559.2707 446.452 487.0775 4949.452 100
order 1288.466 1343.417 1746.7627 1433.221 1500.7865 13768.148 100
For 1 million numbers:
N =...
Why does the C++ STL not provide any “tree” containers?
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ETag vs Header Expires
...he file (HTTP 200) or tell the client to just use their local copy (HTTP 304). An ETag is basically just a checksum for a file that semantically changes when the content of the file changes.
The Expires header is used by the client (and proxies/caches) to determine whether or not it even needs to ...
PHP UML Generator [closed]
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There's also the PHP UML tool available from pear.
PHP_UML:
Can generate UML/XMI files in ve...
What is the quickest way to HTTP GET in Python?
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how to emulate “insert ignore” and “on duplicate key update” (sql merge) with postgresql?
...ww.postgresql.org/docs/9.3/static/plpgsql-control-structures.html, example 40-2 right at the bottom.
That's usually the easiest way. You can do some magic with rules, but it's likely going to be a lot messier. I'd recommend the wrap-in-function approach over that any day.
This works for single row...
Object-orientation in C
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philantphilant
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How to reverse apply a stash?
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$ git commit -am 'Initial commit'
[master (root-commit)]: created 1ff2478: "Initial commit"
1 files changed, 1 insertions(+), 0 deletions(-)
create mode 100644 messages
$ echo Hello again >>messages
$ git stash
$ git status
# On branch master
nothing to commit (working directory clea...
Is there a vr (vertical rule) in html?
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answered Feb 21 '09 at 1:46
Andy BairdAndy Baird
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Extracting the last n characters from a string in R
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AndrieAndrie
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