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How do you detect where two line segments intersect? [closed]
...f r × s = 0 and (q − p) × r ≠ 0, then the two lines are parallel and non-intersecting.
If r × s ≠ 0 and 0 ≤ t ≤ 1 and 0 ≤ u ≤ 1, the two line segments meet at the point p + t r = q + u s.
Otherwise, the two line segments are not parallel but do not intersect....
Multi-statement Table Valued Function vs Inline Table Valued Function
...e compiler cannot use any table statistics on the tables in the MSTVF. So, all things being equal, (which they rarely are), the ITVF will perform better than the MSTVF. In my tests, the performance difference in completion time was negligible however from a statistics standpoint, it was noticeable.
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Is there an expression for an infinite generator?
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for x in iter(int, 1): pass
Two-argument iter = zero-argument callable + sentinel value
int() always returns 0
Therefore, iter(int, 1) is an infinite iterator. There are obviously a huge number of variations on this particular theme (especially once you add lambda into the mix). One va...
Detect URLs in text with JavaScript
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Finally a regex that really works in most obvious case! This one deserves a bookmarking. I tested thousands examples from googles search until i find this.
– Ismael
Jan 16 '15 at 15:11
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How do I concatenate strings and variables in PowerShell?
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This isn't technically concatenation.
– TravisEz13
Jun 14 '16 at 17:59
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Passing a std::array of unknown size to a function
...way to make this work, as one would with plain C-style arrays?
No. You really cannot do that unless you make your function a function template (or use another sort of container, like an std::vector, as suggested in the comments to the question):
template<std::size_t SIZE>
void mulArray(std:...
How to change collation of database, table, column?
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You need to either convert each table individually:
ALTER TABLE mytable CONVERT TO CHARACTER SET utf8mb4
(this will convert the columns just as well), or export the database with latin1 and import it back with utf8mb4.
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How do I show the value of a #define at compile-time?
...ring. When there is more than one component to the argument then they must all be strings so that string concatenation can be applied. The preprocessor can never assume that an unquoted string should be treated as if it were quoted. If it did then:
#define ABC 123
int n = ABC;
would not compile.
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How do you serialize a model instance in Django?
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You can easily use a list to wrap the required object and that's all what django serializers need to correctly serialize it, eg.:
from django.core import serializers
# assuming obj is a model instance
serialized_obj = serializers.serialize('json', [ obj, ])
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Polymorphism in C++
...ecific code selected?
Run time means the compiler must generate code for all the types the program might handle while running, and at run-time the correct code is selected (virtual dispatch)
Compile time means the choice of type-specific code is made during compilation. A consequence of this: say...