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In Python, how do I determine if an object is iterable?
...e a method like isiterable ? The only solution I have found so far is to call
21 Answers
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Can I use __init__.py to define global variables?
I want to define a constant that should be available in all of the submodules of a package. I've thought that the best place would be in in the __init__.py file of the root package. But I don't know how to do this. Suppose I have a few subpackages and each with several modules. How can I access th...
How do I perform the SQL Join equivalent in MongoDB?
...rect. The new $lookup operator added to the aggregation pipeline is essentially identical to a left outer join:
https://docs.mongodb.org/master/reference/operator/aggregation/lookup/#pipe._S_lookup
From the docs:
{
$lookup:
{
from: <collection to join>,
localField: <...
计算统计特征（正态分布）函数及实例 - C/C++ - 清泛网 - 专注C/C++及内核技术
...AX_VAR;
double _ave;
//double _var;
double _sam_stdev;
double _all_stdev;
double _sum;
double _sum_2;
int _count;
double _min_v;
double _max_v;
StdevInfo()
: _ave(0.0)
//, _var(MAX_VAR)
, _sam_stdev(sqrt(MAX_VAR))
, _all_stdev(0.0)
, _sum(0.0)
...
Can't pickle when using multiprocessing Pool.map()
...nsider it "easy" or not;-) is to add the infrastructure to your program to allow such methods to be pickled, registering it with the copy_reg standard library method.
For example, Steven Bethard's contribution to this thread (towards the end of the thread) shows one perfectly workable approach to a...
How to set versionName in APK filename using gradle?
...ind, but doesn't work well with flavors with different version codes. They all end up with same version code.
– weston
May 6 '17 at 15:08
2
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Fastest way to list all primes below N
...4.0 |
| sundaram3 | 416.0 |
+---------------------+-------+
Of all the methods tested, allowing numpy, for n=1000000,
primesfrom2to was the fastest tested.
+---------------------+-------+
| Method | ms |
+---------------------+-------+
| primesfrom2to | 15.9 |
| p...
How can I create a copy of an object in Python?
...would like to create a copy of an object. I want the new object to possess all properties of the old object (values of the fields). But I want to have independent objects. So, if I change values of the fields of the new object, the old object should not be affected by that.
...
node.js global variables?
...
Globals are generally to be avoided, but if you really want to use them. The 3 statements below are all equivalent and will assign a var to the global scope: GLOBAL._ = require('underscore'); global._ = require('underscore'); _ = require('und...
How can I time a code segment for testing performance with Pythons timeit?
...r if you want to average the time elapsed by several runs, you have to manually call the function multiple times (As I think you already do in you example code and timeit does automatically when you set its number argument)
import time
def myfast():
code
n = 10000
t0 = time.time()
for i in ran...