quantopian python library

"This article from the public number" Deng takes you to play Python ", reproduced"Import mathmath.sqrt (8)2.8284271247461903Let's look at the results in PythonMATH.SQRT (8). MATH.SQRT (8)8.000000000000002Ben thought it would get 8.0, but didn't expect to get 8.000000000000002.First, why is this?If our usual tasks often have expressions similar to those in the example above, then directly using Python to cal

The content here is based on Linux process basics and Linux text streaming. The main function of the subprocess package is to execute external commands and programs. For example, I need to use wget to download files. I invoke the wget program in Python. In this sense, the subprocess function is similar to the shell. Subprocess and commonly used encapsulation functions When we run Python, we are creating a

Label:1, sudo apt-get install Python-setuptools 2, sudo apt-get install Libmysqld-dev 3, sudo apt-get install Libmysqlclient-dev 4, sudo apt-get install Python-dev 5, sudo easy_install Mysql-python Under test: In the Python interactive window, import mysqldb try, without error, it proves that the installation is good.

BeautifulSoup Module Introduction and Installation BeautifulSoup BeautifulSoup is a third-party library of Python that extracts data from HTML or XML and is typically used as a parser for Web pages BeautifulSoup Official website: https://www.crummy.com/software/BeautifulSoup/ Official documents: https://www.crummy.com/software/BeautifulSoup/bs4/doc/ English Document: h

"Python/c++ Interface Library comparison" (Swig,boost.python, Pycxx, py++, sip, Weave, Pyrex) http://blog.csdn.net/lainegates/article/details /19565823There are many open-source python/c++ binding tools, search a lot of 岾, here a little summary.SWIG Supports Python 2 and 3 Properly configured, the package

PIL Introduction Pil:python Imaging Library, is already the Python platform de facto image processing standard libraries. The PIL feature is very powerful, but the API is very easy to use.Recently in the writing of some Python crawler need to use PIL this image processing library, but found that the use of PIP can not

http://python.jobbole.com/86397/ Original source: Levinehuang SOURCE Installation The Python third party library can almost always find the source code on GitHub or PyPI. The source package format probably has zip, tar.zip, tar.bz2. Unpack the packets and go into the unpacked folder, usually with a setup.py file. Open the command line and enter the folder. You can install this third

└──scripts.py1 directory, 3 Files[[email Pro Tected] ~]# cat/tmp/scripts.py #!/usr/bin/env pytonimport osimport syspath = Os.path.dirname (__file__) Mod_path = Os.path . Join (Path, "Bin") Sys.path.append (Mod_path) for n in Sys.path:print (n)Execution results[Email protected] ~]# python/tmp/scripts.py/tmp/usr/lib64/python26.zip/usr/lib64/python2.6/usr/lib64/python2.6/ plat-linux2/usr/lib64/python2.6/lib-tk/usr/lib64/python2.6/lib-old/usr/lib64/python

One, python download: https://www.python.org/downloads/Second, the Python module download: http://www.lfd.uci.edu/~gohlke/pythonlibs/#pymssql (common daily packages are available)Python Module (third party libraries): Https://pypi.python.org/pypiThird, the Python Library ins

In general, when we do scientific calculations, the first thing to think of is MATLAB, but, the thought of the MATLAB installation package so big, I have a little to say what.Matplotlib is Python's most famous drawing library, which provides a complete set of command APIs similar to those of MATLAB, and is ideal for interactiveFor mapping. Matplotlib installation can be found in the website link http://matplotlib.org/users/installing.htmlThe installat

Because of the recent intention to learn "machine learning combat" this book, so using Python may be used NumPy, matplotlib, scikit-learn These libraries, so the Internet to find how to install these libraries, look at a number of methods, after trying to find themselves very lucky, Soon it's done, and it's not complicated. Let's get down to business! 1, to the official website https://www.python.org/downloads/download

SolveFirst, the root cause of this problem is that the curses library does not support Windows. So after we download the python (Python comes with the curses library), although we can see the curses library in the python directory

Beautiful SOUP4 Operation why use Beautiful SoupBeautiful soup is a python library that extracts data from HTML or XML files. It is able to use your favorite converter to achieve customary document navigation, find, modify the way the document,is a form of a label to be looked up, somewhat like the form of jquery. Improve efficiency, when we are doing crawler development, the process will use the regular to

Skimage libraries need to rely on NUMPY+MKL and scipy1. Open run, enter cmd return, enter Python return, view Python version2. In https://www.lfd.uci.edu/~gohlke/pythonlibs/#numpy, download the required packages according to your Python version(Because I'm a python 2.7.13 Win32, so I'm under the three below)Numpy?1.13.

-% (levelname) s-% (message) sdatefmt=$ python simple_logging_config.py2018-01-19 21:53:46,216-simpleexample-debug-debug Message2018-01-19 21:53:46,216-simpleexample-info-info Message2018-01-19 21:53:46,216-simpleexample-warning-warn Message2018-01-19 21:53:46,216-simpleexample-error-error Message2018-01-19 21:53:46,216-simpleexample-critical-critical MessageFinally, briefly, how to summarize a module, can be described around the following three point

To deploy a Python script on an online server today, the use of mysqldb, a variety of attempts to download the source code (a variety of dependent libraries are incompatible), Get/yum (this linux is really pure ah these two can not be used) installation, wget download RPM package also not even on the extranet, have failed, and Libmysqlclient-dev and Mysql-python are not very easy to find, there are many ver

Arrow is a lightweight Python library dedicated to time and date, providing a logical and intelligent way to create, manipulate, format, convert time and date. Its design inspiration mainly comes from moment.js.Why design arrow?From a usability standpoint, Python's standard and low-end modules provide complete functionality, but do not work well, and developers struggle with them. Too many modules:

secondsTimeout = 10Socket.setdefaulttimeout (Timeout)# Urllib2.urlopen now uses the default timeout# We have a set in the socket modulereq = Urllib2. Request (' http://www.voidspace.org.uk ')Response = Urllib2.urlopen (req) 12, Cookie urllib2 The processing of cookies is also automatic. If you need to get the value of a Cookie entry, you can do this: Example: Import urllib2 Import cookielib Cookie = cookielib. Cookiejar () opener = Urllib2.build_opener (urllib2. Httpcookieprocessor (cooki

condition object to control the potential lock object.Wait () methodEquivalent to Cond_wait ()Notify_all ()Quite with Cond_broadcast ()Nofify ()Similar to the Notify_all () feature, but only wakes up a waiting thread, not allThreading. Semaphore ObjectSemaphore, which is the count lock. When creating an object, you can pass an integer as the upper limit of the count (Sema = threading. Semaphore (5)).It is similar to lock and has two methods for lock.Threading. Event ObjectWith threading. The co

NumPy itself does not provide much advanced data analysis capabilities, understanding Numpuy arrays and array-oriented computations will help you more efficiently use tools such as PandasPyhton saves a set of values in a list, which can be used as an array. In addition, Python has an array modulo fast, but he does not support multidimensional arrays, whether it is a list or array module has no scientific operation function, not suitable for scientific