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Web-scraping JavaScript page with Python
...a web driver fast enough and easy to get the work done.
Once you have installed Phantom JS, make sure the phantomjs binary is available in the current path:
phantomjs --version
# result:
2.1.1
Example
To give an example, I created a sample page with following HTML code. (link):
<!DOCTYPE ht...
How to replace NaN values by Zeroes in a column of a Pandas Dataframe?
...olumn, select just that column. in this case I'm using inplace=True to actually change the contents of df.
In [12]: df[1].fillna(0, inplace=True)
Out[12]:
0 0.000000
1 0.570994
2 0.000000
3 -0.229738
4 0.000000
Name: 1
In [13]: df
Out[13]:
0 1
0 NaN 0.0000...
How JavaScript closures are garbage collected
...e expected behavior.
From Mozilla's Memory management page: "As of 2012, all modern browsers ship a mark-and-sweep garbage-collector." "Limitation: objects need to be made explicitly unreachable".
In your examples where it fails some is still reachable in the closure. I tried two ways to make it...
node.js fs.readdir recursive directory search
... search using fs.readdir? I realise that we could introduce recursion and call the read directory function with the next directory to read, but am a little worried about it not being async...
...
How to write very long string that conforms with PEP8 and prevent E501
...
Implicit concatenation might be the cleanest solution:
s = "this is my really, really, really, really, really, really," \
" really long string that I'd like to shorten."
Edit On reflection I agree that Todd's suggestion to use brackets rather than line continuation is better for all the reas...
what is .netrwhist?
...riting files across networks. .netrwhist is a history file which maintains all the directories that were modified. So whenever you modify the contents of ~/.vim it adds one entry in .netrwhist
A sample .netrwhist is as shown
let g:netrw_dirhistmax =10
let g:netrw_dirhist_cnt =6
let g:netrw_dirhis...
Print string to text file
...t_file.close()
If you use a context manager, the file is closed automatically for you
with open("Output.txt", "w") as text_file:
text_file.write("Purchase Amount: %s" % TotalAmount)
If you're using Python2.6 or higher, it's preferred to use str.format()
with open("Output.txt", "w") as text...
编译器内部的秘密--微软的编译器是如何解析Try/Catch/Throw的 - C/C++ - 清...
...是一篇介绍如何在x86架构上详细地实现异常处理(exception handling)的手册,只是一篇入门的讨论性文章。本文只是讨论一些处理步骤在理论上应该如何实现,其具体的实现步骤可能跟文章所讨论的并不一致。原文译自:http://www.codep...
What's the common practice for enums in Python? [duplicate]
... Python.
The best way I've found to emulate them is by overridding _ str _ and _ eq _ so you can compare them and when you use print() you get the string instead of the numerical value.
class enumSeason():
Spring = 0
Summer = 1
Fall = 2
Winter = 3
def __init__(self, Type):
...
How to keep a Python script output window open?
...a few options:
Run the program from an already-open terminal. Open a command prompt and type:
python myscript.py
For that to work you need the python executable in your path. Just check on how to edit environment variables on Windows, and add C:\PYTHON26 (or whatever directory you installed pyt...
