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How to execute a Python script from the Django shell?
...es, it's a good idea to set it up as a custom command ie
$ ./manage.py my_command
to do this create a file in a subdir of management and commands of your app, ie
my_app/
__init__.py
models.py
management/
__init__.py
commands/
__init__.py
my_co...
How do I print the type of a variable in Rust?
...r
|
= note: expected type `()`
found type `{float}`
Or call an invalid method:
let mut my_number = 32.90;
my_number.what_is_this();
error[E0599]: no method named `what_is_this` found for type `{float}` in the current scope
--> src/main.rs:3:15
|
3 | my_number.what_is_...
Function for Factorial in Python
...The concept used here is called recursion ( en.wikipedia.org/wiki/Recursion_(computer_science) ) - a function calling itself is perfectly fine and often useful.
– schnaader
Nov 7 '14 at 10:06
...
What is __pycache__?
...'s files, respectively.
As a programmer, you can largely just ignore it... All it does is make your program start a little faster. When your scripts change, they will be recompiled, and if you delete the files or the whole folder and run your program again, they will reappear (unless you specificall...
iOS开发过程中的各种tips - 更多技术 - 清泛网 - 专注C/C++及内核技术
...直接在介绍AFNetworking的时候详解吧。
25.使用NSURLConnection下载数据
1. 创建对象
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:@"http://www.baidu.com"]];
[NSURLConnection connectionWithRequest:request delegate:self];
2. NSURLCon...
Why should hash functions use a prime number modulus?
...
Usually a simple hash function works by taking the "component parts" of the input (characters in the case of a string), and multiplying them by the powers of some constant, and adding them together in some integer type. So for e...
What is the difference between “def” and “val” to define a function
...ion every time (new instance of Function1).
def even: Int => Boolean = _ % 2 == 0
even eq even
//Boolean = false
val even: Int => Boolean = _ % 2 == 0
even eq even
//Boolean = true
With def you can get new function on every call:
val test: () => Int = {
val r = util.Random.nextInt
...
Post JSON using Python Requests
...ost('http://httpbin.org/post', json={"key": "value"})
>>> r.status_code
200
>>> r.json()
{'args': {},
'data': '{"key": "value"}',
'files': {},
'form': {},
'headers': {'Accept': '*/*',
'Accept-Encoding': 'gzip, deflate',
'Connection': 'close',
...
check if variable is dataframe
...rame
Yes: isinstance(x, pd.DataFrame)
And don't even think about
if obj.__class__.__name__ = 'DataFrame':
expect_problems_some_day()
isinstance handles inheritance (see What are the differences between type() and isinstance()?). For example, it will tell you if a variable is a string (eithe...
Detect if device is iOS
... are changed and differentiating between iPad and MacOS seems possible, so all answers below needs to take that into account now.
This might be the shortest alternative that also covers iOS 13:
function iOS() {
return [
'iPad Simulator',
'iPhone Simulator',
'iPod Simulator',
'iPad'...