How-to articles, tricks, and solutions about PYTHON

In Python, you can check if a variable is not equal to None using the is not operator.

In Python, the "null" object is called None.

Here is a code snippet that demonstrates how to use the open() function in Python to create a new file if it does not already exist:

Here is an example code snippet that demonstrates how to use the groupby() method in pandas to group a DataFrame by two columns and get the counts for each group:

To set the name of the index column in a pandas DataFrame, you can use the .rename_axis() method or the .index.name attribute.

Here is an example of how to use the pd.merge() function to merge two DataFrames in pandas:

Here is an example of how to parse boolean values with argparse in Python:

Here is an example of a Python function that can be used to detect peaks in a 2D array:

Check the location of pg_config: Open a terminal and run the command "which pg_config".

This error message occurs when pip is unable to verify the certificate of the website it is trying to connect to.

You can use pip to install a package from a git repository and specify a branch by using the following syntax:

This error occurs when the mysql-config command is not in the system's PATH.

Here is an example of how to use pip to install a specific version of a package, rather than using a cached version:

Here is a code snippet that shows how to plot a graph with logarithmic scales for both the x and y axes in Python using the Matplotlib library:

You can use the .head() method to print the first few rows of a Pandas Series or DataFrame in a "pretty" format.

Here is an example of how to print multiple arguments in Python:

In Python, you can use the built-in open() function to create a text file and write a string to it.

Here is an example of how to print a list of lists (a 2D list) as tabular data using Python:

To declare a custom exception in Python, you can create a new class that inherits from the built-in Exception class.

The purpose of "%matplotlib inline" in Python is to display matplotlib plots within the Jupyter notebook.

In Python, you can put a simple if-then-else statement on one line using the ternary operator, which is represented by the "?" symbol.

The proper way to check if a variable x is not None in Python is to use if x is not None.

You can use the len() function to count the number of elements in a list.

This error message is indicating that you are trying to iterate over an object of type 'int', which is not iterable (i.e.

This error occurs when you are trying to access a variable before it has been assigned a value.