大约有 44,000 项符合查询结果（耗时：0.0255秒） [XML]
What is the difference between class and instance attributes?
...> a.foo.append(5)
>>> b.foo
[5]
>>> class A:
... def __init__(self): self.foo = []
>>> a, b = A(), A()
>>> a.foo.append(5)
>>> b.foo
[]
share
|
...
Split data frame string column into multiple columns
...
Use stringr::str_split_fixed
library(stringr)
str_split_fixed(before$type, "_and_", 2)
share
|
improve this answer
|
...
List directory tree structure in python?
...
Here's a function to do that with formatting:
import os
def list_files(startpath):
for root, dirs, files in os.walk(startpath):
level = root.replace(startpath, '').count(os.sep)
indent = ' ' * 4 * (level)
print('{}{}/'.format(indent, os.path.basename(root)))
...
What's a correct and good way to implement __hash__()?
What's a correct and good way to implement __hash__() ?
6 Answers
6
...
How to import the class within the same directory or sub directory?
...
Python 2
Make an empty file called __init__.py in the same directory as the files. That will signify to Python that it's "ok to import from this directory".
Then just do...
from user import User
from dir import Dir
The same holds true if the files are in a...
Import a file from a subdirectory?
....org/tutorial/modules.html
In short, you need to put a blank file named
__init__.py
in the "lib" directory.
share
|
improve this answer
|
follow
|
...
Using logging in multiple modules
...ave a logger defined like this:
import logging
logger = logging.getLogger(__name__)
near the top of the module, and then in other code in the module do e.g.
logger.debug('My message with %s', 'variable data')
If you need to subdivide logging activity inside a module, use e.g.
loggerA = loggin...
What is __declspec and when do I need to use it?
I have seen instances of __declspec in the code that I am reading. What is it? And when would I need to use this construct?
...
Is it possible to print a variable's type in standard C++?
...at I'm recommending below is:
template <typename T> std::string type_name();
which would be used like this:
const int ci = 0;
std::cout << type_name<decltype(ci)>() << '\n';
and for me outputs:
int const
<disclaimer> I have not tested this on MSVC. </disclai...
What's the difference between globals(), locals(), and vars()?
... the same dict each time - it's attached to the stack frame object as its f_locals attribute. The dict's contents are updated on each locals() call and each f_locals attribute access, but only on such calls or attribute accesses. It does not automatically update when variables are assigned, and assi...