大约有 1,700 项符合查询结果（耗时：0.0173秒） [XML]
What's the bad magic number error?
...b3: 62101
2.5b3: 62111
2.5c1: 62121
2.5c2: 62131
2.6a0: 62151
2.6a1: 62161
2.7a0: 62171
share
|
improve this answer
|
follow
|
...
What is the fastest way to check if a class has a function defined?
I'm writing an AI state space search algorithm, and I have a generic class which can be used to quickly implement a search algorithm. A subclass would define the necessary operations, and the algorithm does the rest.
...
How do I find the location of Python module sources?
... 2.0+ is available online at http://hg.python.org/cpython/file/X.Y/ (e.g., 2.7 or 3.3). So, once you discover that inspect.getfile(datetime) is a .so or .pyd file like /usr/local/lib/python2.7/lib-dynload/datetime.so, you can look it up inside the Modules directory. Strictly speaking, there's no way...
Reading a huge .csv file
I'm currently trying to read data from .csv files in Python 2.7 with up to 1 million rows, and 200 columns (files range from 100mb to 1.6gb). I can do this (very slowly) for the files with under 300,000 rows, but once I go above that I get memory errors. My code looks like this:
...
builtins.TypeError: must be str, not bytes
I've converted my scripts from Python 2.7 to 3.2, and I have a bug.
2 Answers
2
...
How can I open multiple files using “with open” in Python?
...
As of Python 2.7 (or 3.1 respectively) you can write
with open('a', 'w') as a, open('b', 'w') as b:
do_something()
In earlier versions of Python, you can sometimes use
contextlib.nested() to nest context managers. This won't work...
Rename an environment with virtualenvwrapper
...
if you do:
$ ack-grep -ai doors ~/.virtualenvs/django/bin
you'll notice that will have doors as location and not django, you'll to change each file with the new location.
solution:
after renamed the folder execute the command below.
$ sed -i "...
Add text to Existing PDF using Python
...
Example for [Python 2.7]:
from pyPdf import PdfFileWriter, PdfFileReader
import StringIO
from reportlab.pdfgen import canvas
from reportlab.lib.pagesizes import letter
packet = StringIO.StringIO()
# create a new PDF with Reportlab
can = canvas...
Pickle or json?
...cfa959a70/pickle_vs_json.py
python pickle_vs_json.py
Results with python 2.7 on a decent 2015 Xeon processor:
Dir Entries Method Time Length
dump 10 JSON 0.017 1484510
load 10 JSON 0.375 -
dump 10 Pickle 0.011 1428790
load 10 Pickle 0.098 -
dump 20 JSON ...
Can a variable number of arguments be passed to a function?
... Not sure how you got myfunc(abc=123, def=456) to work, but in mine (2.7), 'def' can't be passed in this function without getting a SyntaxError. I assume this is because def has meaning in python. Try myfunc(abc=123,fgh=567) instead. (Otherwise, great answer and thanks for it!)
...