Type Conversions

There may be times when we need to change data from one type to another. Here are some scenarios where this conversion is necessary:

• Reading data from CSV files: When reading data from CSV files, Python reads each entry as a string. Depending on the data types in each column, you might need to convert these strings to integers, floats, or Booleans.

• Exchanging data using APIs: When exchanging data using APIs, data might be received in a specific format (e.g., JSON). You might need to convert the received data (strings or dictionaries) to the appropriate Python data types (lists, integers, etc.) for further use in your application.

• Processing web form data: Data submitted through web forms is often in string format. You might need to convert this string data to integers (for age or quantity), floats (for prices or measurements), or Booleans (for yes/no checkboxes) before performing calculations or storing it in a database.

• Handling configuration files: Configuration files might store settings as strings. To be used correctly in the application, these strings need to be converted to the appropriate data types (e.g., Booleans for feature flags, integers for port numbers).

• Database operations: When retrieving data from a database, data types might need to be converted from strings to their appropriate types (e.g., dates, decimals) to perform calculations, comparisons, or data manipulation.

• Data analysis and visualization: Data loaded into data analysis tools (like pandas) from various sources might be in string format. Converting these strings to appropriate data types (e.g., datetime for timestamps, floats for numerical analysis) is crucial for accurate analysis and visualization.

In Python, type conversion is usually an easy process since the compiler can automatically convert data between different types in order to avoid errors. However, there are built-in functions that allow us to perform explicit type conversions.

You may come across another term called “type casting.” It is the same thing. It finds its origins in programming languages like C++. Though not commonly used, this term is acceptable in the Python community as well.

Implicit conversion

Python performs implicit type conversion, also known as type coercion, where it automatically converts one data type to another without the programmer's intervention. This typically happens in certain operations and expressions.

Numeric conversion (int to float)

When an integer is added to a float, Python implicitly converts the integer to a float to perform that operation. Once the operation has been completed, the value inside the variable would still be an integer.