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Why were pandas merges in python faster than data.table merges in R in 2012?
...unique strings (levels) is large: 10,000.
Does Rprof() reveal most of the time spent in the call sortedmatch(levels(i[[lc]]), levels(x[[rc]])? This isn't really the join itself (the algorithm), but a preliminary step.
Recent efforts have gone into allowing character columns in keys, which should ...
What are the effects of exceptions on performance in Java?
...ll registers of the CPU are written to the stack (which already takes some time) and possibly some other data needs to be created... all this already happens in the try statement. The throw statement needs to unwind the stack and restore the values of all registers (and possible other values in the ...
Database development mistakes made by application developers [closed]
...priate indices
This is a relatively easy one but still it happens all the time. Foreign keys should have indexes on them. If you're using a field in a WHERE you should (probably) have an index on it. Such indexes should often cover multiple columns based on the queries you need to execute.
2. N...
Scroll to a div using jquery
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It doesn't scroll at first click. :/ I click it second time and it works.
– Burak Karakuş
Sep 26 '14 at 14:24
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How to make the window full screen with Javascript (stretching all over the screen)
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This happened last time a site used code like that and I didn't block it: dorward.me.uk/tmp/fullscreen.jpeg
– Quentin
Apr 8 '10 at 14:39
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Powershell v3 Invoke-WebRequest HTTPS error
...allback functionality), and doesn't attempt to load the same code multiple times within the same powershell session:
if (-not ([System.Management.Automation.PSTypeName]'ServerCertificateValidationCallback').Type)
{
$certCallback=@"
using System;
using System.Net;
using System.Net.Securi...
Commands executed from vim are not recognizing bash command aliases
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Then add this to your .vimrc so the aliases file is actually read each time you run a shell command from within vim:
let $BASH_ENV = "~/.bash_aliases"
This solution was suggested by "Jakob". See the link below for the original. I tested this on Mac OS X 10.9 and it worked flawlessly!
vim --...
How far can memory leaks go?
I've run into memory leaks many times. Usually when I'm malloc -ing like there's no tomorrow, or dangling FILE * s like dirty laundry. I generally assume (read: hope desperately) that all memory is cleaned up at least when the program terminates. Are there any situations where leaked memory won't ...
ElasticSearch: Unassigned Shards, how to fix?
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Thanks a ton! It saved precious time!!
– Sathish
May 17 '18 at 8:42
The scr...
CSS: Animation vs. Transition
...th are very modern.
My rule of thumb is if I use the same transition three times, it should probably be an animation. This is easier to maintain and alter in the future. But if you are only using it once, it is more typing to make the animation and maybe not worth it.
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