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No mapping found for field in order to sort on in ElasticSearch
... I still have the problem but I want the documents to be in the results in all cases even if they don't have the attribute.
– c4k
Oct 27 '13 at 15:47
...
Delete column from SQLite table
...the columns, whereas something like the accepted answer seems to result in all columns to be of type TEXT.
– Uwe Keim
Jul 10 '17 at 15:05
2
...
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 = ...
Python: most idiomatic way to convert None to empty string?
...
If you actually want your function to behave like the str() built-in, but return an empty string when the argument is None, do this:
def xstr(s):
if s is None:
return ''
return str(s)
...
Is bool a native C type?
... in the current C - C99, but not in C89/90.
In C99 the native type is actually called _Bool, while bool is a standard library macro defined in stdbool.h (which expectedly resolves to _Bool). Objects of type _Bool hold either 0 or 1, while true and false are also macros from stdbool.h.
Note, BTW, t...
print call stack in C or C++
Is there any way to dump the call stack in a running process in C or C++ every time a certain function is called? What I have in mind is something like this:
...
How can I prevent SQL injection in PHP?
...is way it is impossible for an attacker to inject malicious SQL.
You basically have two options to achieve this:
Using PDO (for any supported database driver):
$stmt = $pdo->prepare('SELECT * FROM employees WHERE name = :name');
$stmt->execute([ 'name' => $name ]);
foreach ($stmt as $...
Can you run GUI applications in a Docker container?
...
You can simply install a vncserver along with Firefox :)
I pushed an image, vnc/firefox, here: docker pull creack/firefox-vnc
The image has been made with this Dockerfile:
# Firefox over VNC
#
# VERSION 0.1
# DOCKER-VERSION ...
Max length UITextField
... that can be entered into a UITextField using swift? , I saw that if I use all 10 characters, I can't erase the character too.
...
correct way to define class variables in Python [duplicate]
... being init always executed after the object is created, it becomes practically equal to define variables outside of init, right?
– jeanc
Jan 29 '12 at 21:33
2
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