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How to use python 3.5.1 with a MySQL database

I did the steps below with Python 3.5.1 and it works: Download driver from here Driver installation in cmd, in this folder Python\Python35\PyMySQL-0.7.4\pymysqlpython setup.py build python setup.py install Copy folder Python\Python35\PyMySQL-0.7.4\pymysql to Python\Python35\pymysql Sample code in python IDEimport pymysql import pymysql.cursors conn= pymysql.connect(host=’localhost’,user=’user’,password=’user’,db=’testdb’,charset=’utf8mb4′,cursorclass=pymysql.cursors.DictCursor) a=conn.cursor() sql=’CREATE TABLE `users` (`id` int(11) NOT NULL AUTO_INCREMENT,`email` varchar(255) NOT NULL,`password` varchar(255) … Read more

Using print() (the function version) in Python2.x

Consider the following expressions: They’re equivalent. In the same way, with a statement: are also equivalent. Notice that if you change your print function to: You’ll notice a difference between python 2 and python 3. With python 2, the (…,…) is interpteted as a tuple since print is a statement whereas in python 3, it’s a function … Read more

What does the “w” mean in open(filename, “w”)?

w stands for writing permission for the opened file Looking at the signature we can (often) understand what each argument does more info here

How do I compile my Python 3 app to an .exe?

cx_Freeze does this but creates a folder with lots of dependencies. py2exe now does this and, with the –bundle-files 0 option, creates just one EXE, which is probably the best solution to your question. UPDATE: After encountering third-party modules that py2exe had trouble “finding”, I’ve moved to pyinstaller as kotlet schabowy suggests below. Both have ample documentation … Read more

Python MySQLdb not importing

You needed to install the module with pip pip install mysql-python

python-dev installation error: ImportError: No module named apt_pkg

I met this problem when doing sudo apt-get update. My env is debian8, with python2.7 + 3.4(default) + 3.5. The following code will only re-create a apt_pkg….so file for python 3.5 The following code solved my problem, Replace {your-version-number} appropriately. CAUTION, the following will create a symlink from apt_pkg37m to apt_pkg36m. make sure you are linking to the correct, or at … Read more

vectorize conditional assignment in pandas dataframe

One simple method would be to assign the default value first and then perform 2 loc calls: If you wanted to use np.where then you could do it with a nested np.where: So here we define the first condition as where x is less than -2, return 1, then we have another np.where which tests the other condition where x is greater … Read more

ValueError: Must pass DataFrame with boolean values only

You’re trying to use a different shaped df to mask your df, this is wrong, additionally the way you’re passing the conditions is being used incorrectly. When you compare a column or series in a df with a scalar to produce a boolean mask you should pass just the condition, not use this successively. you … Read more

SMTP AUTH extension not supported by server

a connection is required before login and sendemail.

ValueError: Cannot set a frame with no defined index and a value that cannot be converted to a Series

You have a column of ragged lists. Your only option is to assign a list of lists, and not an array of lists (which is what .value gives).

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