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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 = ...
String literals and escape characters in postgresql
...the escape string syntax for escapes, e.g., E'\r\n'.
INSERT 0 1
milen=> select * from EscapeTest;
text
------------------------
This will be inserted
This will not be
(1 row)
milen=>
share
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Django, creating a custom 500/404 error page
... for some reason request.user appears fine in the 404 template, but not at all in the 500 template (and they are almost identical) -- posted question on this here: stackoverflow.com/questions/26043211/…
– Gravity Grave
Sep 25 '14 at 16:13
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Finding quaternion representing the rotation from one vector to another
...
Be aware that this does not handle the case of parallel vectors (both in the same direction or pointing in opposite directions). crossproduct will not be valid in these cases, so you first need to check dot(v1, v2) > 0.999999 and dot(v1, v2) < -0.999999, respectively, ...
LINQ Ring: Any() vs Contains() for Huge Collections
... result = context.Projects.Where(x => lstBizIds.Contains(x.businessId)).Select(x => x.projectId).ToList();
This will give the query
SELECT Id
FROM Projects
INNER JOIN (VALUES (1), (2), (3), (4), (5)) AS Data(Item) ON Projects.UserId = Data.Item
while Any() on the other hand always iterate t...
Why do you need to create a cursor when querying a sqlite database?
...les traversal over the records in a database". For example c.execute('''SELECT * FROM users''') returns an iterator that you can call fetchall() on (or another cursor method). Some SQL queries return empty iterators, but that should be expected, not surprising.
– Powers
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Download attachments using Java Mail
Now that I`ve downloaded all the messages, and store them to
4 Answers
4
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Python string.join(list) on object array rather than string array
...riments says that the list comprehension one can be a good 60% faster on small lists (experiment run 10^6 times on a list of three object()s). However, their performance is similar on big lists (2nd experiment run once on a 10^7 objects() list).
– gozzilli
Mar ...
Remove last item from array
..., -1) will not. Pop is of course faster but may not be always suitable for all needs.
– adelriosantiago
Sep 23 '17 at 0:40
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How do I get an object's unqualified (short) class name?
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You can do this with reflection. Specifically, you can use the ReflectionClass::getShortName method, which gets the name of the class without its namespace.
First, you need to build a ReflectionClass instance, and then call the getShortName method of that instance:...