When I connect to my local PostgreSQL database server with command $ psql postgres ‘postgres’ I encounter the error message psql: FATAL: Peer authentication failed for user “postgres”. :~$ psql postgres ‘postgres’ psql: FATAL: Peer authentication failed for user “postgres” After investigating I finally find the solution to fix this error. This error is because […]
PostgreSQL is a popular open-source RDBMS database widely used in programming. It is supported by multiple programming languages such as python, java, etc. This article will tell you how to install and manage PostgreSQL on Ubuntu Linux both with command line and pgAdmin3 ( a graphical user interface tool).
Python dictionary is something like java map. It can hold key value pair values. This example will tell you some basic python dictionary object operations. It includes how to create, add, change and remove python dictionary key and values.
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This article will tell you how to create a WordPress website on BlueHost. And how to reinstall the WordPress website if you encounter errors.
How To Setup WordPress Website On Bluehost Read More »
When you operate on a python string, it will create a new python string based on the original string. The original string value will not be changed. This article will list some python string operation example.
Python String Function Examples Read More »
Python list is a sequence of objects which is similar to other programming languages’ arrays. Python list object is mutable, resizable and it can hold any data type object. This example will tell you how to create a python list object and how to operate on it to implement add, append, extend, remove, change, get
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In python there are only two boolean value : True or False. And all Python object can be expressed as Boolean value, regardless of their own value. For example all python variable which value is 0’s boolean value is False, all python variable which value is not 0’s boolean value is True. Similarly, empty container
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This article will show you how to use matplotlib to draw single-line plot graphs in Python and iPython.
How To Use Matplotlib In Python And Ipython To Draw Single Line Plot Example Read More »
sys.argv[] is used to get python command line arguments. sys.argv[0] ‘s value is the file path of the python source code file that is running. For example, if you run python test_sys_arg.pyin a terminal, then sys.argv[0]‘s value is test_sys_arg.py. This article will give you two example about how to use sys.argv[] to get command line
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When I run my python script code, I meet an error like this IndentationError: unindent does not match any outer indentation level. This error is so strange and hard to find the reason. After some investigation, I finally find the solution.