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Fastest way to replace NAs in a large data.table
....805 12.301 134.985
system.time(a_andrie = f_andrie(dt1))
Error: cannot allocate vector of size 305.2 Mb
Timing stopped at: 14.541 7.764 68.285
system.time(f_dowle(dt1))
user system elapsed
7.452 4.144 19.590 # EDIT has faster than this
identical(a_gdata, dt1)
[1] TRUE
Note th...
Is there a difference between foreach and map?
...important point to mention (this is particularly true in Scala) is that a call to map does not result in the execution of its underlying logic until when the expected transformed list is summoned. In contrast, foreach's operation is computed immediately.
– solimant
...
How to keep keys/values in same order as declared?
...ry that I declared in a particular order and want to keep it in that order all the time. The keys/values can't really be kept in order based on their value, I just want it in the order that I declared it.
...
Custom method names in ASP.NET Web API
...I want to have a method named Authenticate. I see examples of how to do GetAll, GetOne, Post, and Delete, however what if I want to add extra methods into these services? For instance, my UsersService should have a method called Authenticate where they pass in a username and password, however it doe...
Get the current URL with JavaScript?
All I want is to get the website URL. Not the URL as taken from a link. On the page loading I need to be able to grab the full, current URL of the website and set it as a variable to do with as I please.
...
How to draw a dotted line with css?
... lot of cruft that is no longer required for modern browsers. I have personally tested the following CSS on all browsers as far back as IE8, and it works perfectly.
hr {
border: none;
border-top: 1px dotted black;
}
border: none must come first, to remove all the default border styling...
What's the “Content-Length” field in HTTP header?
... Combine this answer with the answer from Tom Cabanski and you have all the information you need. In case of text you can count the number of characters since ASCII is 8 bit.
– hcpl
Sep 24 '12 at 8:45
...
C++ equivalent of StringBuffer/StringBuilder?
...f after profiling your code you discover this makes an improvement.
I normally use either std::string or std::stringstream. I have never had any problems with these. I would normally reserve some room first if I know the rough size of the string in advance.
I have seen other people make their ow...
Prevent onmouseout when hovering child element of the parent absolute div WITHOUT jQuery
...Listener('mouseout',onMouseOut,true);
I made a quick JsFiddle demo, with all the CSS and HTML needed, check it out...
EDIT FIXED link for cross-browser support http://jsfiddle.net/RH3tA/9/
NOTE that this only checks the immediate parent, if the parent div had nested children then you have to s...
Volatile Vs Atomic [duplicate]
...icInteger and AtomicReference, provide a wider variety of operations atomically, specifically including increment for AtomicInteger.
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