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Circle line-segment collision detection algorithm?
... exdx + eydy - dxh - dyk ) +
ex2 + ey2 -
2exh - 2eyk + h2 + k2 - r2 = 0
Finally,
t2( _d * _d ) + 2t( _e * _d - _d * _c ) + _e * _e - 2( _e*_c ) + _c * _c - r2 = 0
*Where _d is the vector d and * is the dot product.*
And then,
t2( _d * _d ) + 2t( _d * ( _e - _c ) ) + ( _e - _c ) * ( _e - _c ) - r2 = ...
How to deal with floating point number precision in JavaScript?
...at depends on what kind of
calculations you’re doing.
If you really need your results to add up exactly, especially when you
work with money: use a special decimal
datatype.
If you just don’t want to see all those extra decimal places: simply
format your result rounded to a fix...
Cannot resolve the collation conflict between “SQL_Latin1_General_CP1_CI_AS” and “Latin1_General_CI_
...lations are needed and used when ordering and comparing strings. It's generally a good idea to have a single, unique collation used throughout your database - don't use different collations within a single table or database - you're only asking for trouble....
Once you've settled for one single col...
MySQL query String contains
...
Quite simple actually:
mysql_query("
SELECT *
FROM `table`
WHERE `column` LIKE '%{$needle}%'
");
The % is a wildcard for any characters set (none, one or many). Do note that this can get slow on very large datasets so if your database grow...
What is the most efficient string concatenation method in python?
... idiomatic and thus easier for other python programmers to understand.
Finally, the golden rule of optimization: don't optimize unless you know you need to, and measure rather than guessing.
You can measure different methods using the timeit module. That can tell you which is fastest, instead of r...
using lodash .groupBy. how to add your own keys for grouped output?
...t hard to wrap my head around. Can you explain the steps in between, especially the pairing and zipping (and the double zip, since _.object is an alias for _.zipObject).
– Benny Bottema
Jul 31 '15 at 9:17
...
What is the type of lambda when deduced with “auto” in C++11?
...
The type of a lambda expression is unspecified.
But they are generally mere syntactic sugar for functors. A lambda is translated directly into a functor. Anything inside the [] are turned into constructor parameters and members of the functor object, and the parameters inside () are turned ...
Where is SQL Server Management Studio 2012?
... SQL Server 2008 R2 and Visual Studio 2008 and 2010 on my laptop. I've installed SQL Server 2012 and have finally got SQL Server Data Tools to show up, so that I can create SSRS reports in Visual Studio 2010.
...
How to Load an Assembly to AppDomain with all references recursively?
...e I wrote to solve this problem: github.com/jduv/AppDomainToolkit. Specifically, look at the LoadAssemblyWithReferences method in this class: github.com/jduv/AppDomainToolkit/blob/master/AppDomainToolkit/…
– Jduv
Mar 14 '13 at 14:44
...
Difference between staticmethod and classmethod
...
Maybe a bit of example code will help: Notice the difference in the call signatures of foo, class_foo and static_foo:
class A(object):
def foo(self, x):
print "executing foo(%s, %s)" % (self, x)
@classmethod
def class_foo(cls, x):
print "executing class_foo(%s, %s...