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John Carmack's Unusual Fast Inverse Square Root (Quake III)
...
I would imagine where the first guess can be derived from justifiable constants, rather than being seemingly arbitrary. Although if you want a technical description, you can look it up. I'm not a mathematician, and a semantic discussion about mathematical terminology doesn't be...
dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...ime, especially since your data are already factored, you can use complete from "tidyr" to get what you might be looking for:
library(tidyr)
df %>%
group_by(b) %>%
summarise(count_a=length(a)) %>%
complete(b)
# Source: local data frame [3 x 2]
#
# b count_a
# (fctr) (int)...
Difference between Grunt, NPM and Bower ( package.json vs bower.json )
...like that without adding them to the file that manages dependencies (apart from installing command line tools globally)?
Always. Just because of comfort. When you add a flag (--save-dev or --save) the file that manages deps (package.json) gets updated automatically. Don't waste time by editing dep...
Why XML-Serializable class need a parameterless constructor
...on, because it means that you cannot have any readonly members initialized from constructor parameters.
In addition to all this, the XmlSerializer class could have been written in such a way as to allow even deserialization of classes without parameterless constructors. All it would take would be ...
Why '&&' and not '&'?
... false and the evaluation of the rest (op.CanExecute()) is skipped.
Apart from this, technically, they are different, too:
&& and || can only be used on bool whereas & and | can be used on any integral type (bool, int, long, sbyte, ...), because they are bitwise operators. & is the ...
Looking for a clear definition of what a “tokenizer”, “parser” and...
... other token is an equality operator.
A parser takes the stream of tokens from the lexer and turns it into an abstract syntax tree representing the (usually) program represented by the original text.
Last I checked, the best book on the subject was "Compilers: Principles, Techniques, and Tools" us...
Why should C++ programmers minimize use of 'new'?
...ven if the stack could hold the entire file contents, you could not return from a function and keep the allocated memory block.
Why dynamic allocation is often unnecessary
In C++ there's a neat construct called a destructor. This mechanism allows you to manage resources by aligning the lifetime o...
Javascript web app and Java server, build all in Maven or use Grunt for web app?
...can use the Maven ant-run plugin, you can run an ant exec task and call it from Maven or best of all you can just use the maven exec task.
Below is the code to integrate this into the Maven lifecycle using the exec plugin if this is helpful to anybody.
<plugin>
<groupId>org.c...
How to declare a structure in a header that is to be used by multiple files in c?
...op of the header and then declare variables as GLOBAL struct a myAValue;. From most source files, you arrange for the #define GLOBAL extern version to be used (declaring the variables) and from exactly one source file it causes the empty define to be used so the variables are defined.
...
How to avoid null checking in Java?
...n environment, although my testing has shown next to no performance impact from assertions.
Not using assertions in this case is OK because the code will just fail, which is what will happen if you use assertions. The only difference is that with assertions it might happen sooner, in a more-meanin...