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Nested defaultdict of defaultdict
...
For an arbitrary number of levels:
def rec_dd():
return defaultdict(rec_dd)
>>> x = rec_dd()
>>> x['a']['b']['c']['d']
defaultdict(<function rec_dd at 0x7f0dcef81500>, {})
>>> print json.dumps(x)
{"a": {"b": {"c": {"d": {}}}}}
...
Linux command or script counting duplicated lines in a text file?
...3
}
or you can use a simple one-liner:
$ cat filename | python3 -c 'print(__import__("json").dumps(__import__("collections").Counter(map(str.strip, __import__("fileinput").input())), indent=2))'
share
|
...
php $_POST array empty upon form submission
...ed to share it as it cost me much time.
When using JSON content-type the $_POST array will not populate (only with multi-part forms I believe)
Here is what did work to correct the issue:
$rest_json = file_get_contents("php://input");
$_POST = json_decode($rest_json, true);
hope this helps someo...
Does Java 8 provide a good way to repeat a value or function?
...Core2Duo)
Benchmark Mode Samples Mean Mean error Units
c.s.q.SO18532488.ncopies thrpt 5 7.547 2.904 ops/s
c.s.q.SO18532488.range thrpt 5 0.317 0.064 ops/s
There is a fair amount of variance in the ncopies ...
Updating MySQL primary key
I have a table user_interactions with 4 columns:
3 Answers
3
...
How to check the extension of a filename in a bash script?
... In bash, this will produce a "[: ==: unary operator expected" error unless you put quotes around the first variable. So if [ "${file: -4}" == ".txt" ] instead.
– Giles B
Oct 18 '19 at 15:03
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What is the Python equivalent of Matlab's tic and toc functions?
...) - t
I have a helper class I like to use:
class Timer(object):
def __init__(self, name=None):
self.name = name
def __enter__(self):
self.tstart = time.time()
def __exit__(self, type, value, traceback):
if self.name:
print('[%s]' % self.name,)
...
Static class initializer in PHP
...
* @var Singleton
*/
private static $instance;
private function __construct()
{
// Your "heavy" initialization stuff here
}
public static function getInstance()
{
if ( is_null( self::$instance ) )
{
self::$instance = new self();
}
return self::$instance;...
In a django model custom save() method, how should you identify a new object?
...
Updated: With the clarification that self._state is not a private instance variable, but named that way to avoid conflicts, checking self._state.adding is now the preferable way to check.
self.pk is None:
returns True within a new Model object, unless the object...
mongodb count num of distinct values per field/key
...}
},
{ $unwind: "$keywords" },
{
$group: {
_id: {$toLower: '$keywords'},
count: { $sum: 1 }
}
},
{
$match: {
count: { $gte: 2 }
}
},
{ $sort : { count : -1} },
{ $limit : 100 }
]);
that give result ...