Python Type Conversion and Type Casting

In this article, you will learn about the python type conversion and type casting and the uses of type conversion. Before learning conversion and casting, you should have knowledge about Python Data Types.

Type Conversion

The process of converting the value of one data type (integer, string, float, etc.) to another data type is called type conversion. Python has two types of type conversion and type casting.

1. Implicit Conversion
2. Explicit Conversion

Implicit Conversion

In Implicit conversion, Python automatically converts one data type to another data type. This process doesn’t need any user involvement. Let’s see an example where Python promotes the conversion of the lower data type (integer) to the higher data type (float) to avoid data loss.

Example 1: Converting integer to float

When we run the above program, the output will be:

In the above program,

• We add two variables num_int and num_flo, storing the value in num_new.
• We will look at the data type of all three objects respectively.
• In the output, we can see the data type of num_int is an integer while the data type of num_flo is a float.
• Also, we can see the num_new has a float data type because Python always converts smaller data types to larger data types to avoid the loss of data.

Now, let’s try adding a string and an integer, and see how Python deals with it.

Example 2: Addition of string(higher) data type and integer(lower) datatype

When we run the above program, the output will be:

In the above program,

• We add two variables num_int and num_str.
• As we can see from the output, we got TypeError. Python is not able to use Implicit Conversion in such conditions.
• However, Python has a solution for these types of situations which is known as Explicit Conversion.

Explicit Conversion

In Explicit Conversion, users convert the data type of an object to the required data type. We use predefined functions like int(), float(), str(), etc to perform explicit type conversion. This type of conversion is also called typecasting because the user casts (changes) the data type of the objects. Syntax :

Typecasting can be done by assigning the required data type function to the expression.

Example 3: Addition of string and integer using explicit conversion

When we run the above program, the output will be:

In the above program,

• We add num_str and num_int variables.
• We converted num_str from string(higher) to integer(lower) type using int() function to perform the addition.
• After converting num_str to an integer value, Python is able to add these two variables.
• We got the num_sum value and data type to be an integer.

Key Points to Remember

1. Type Conversion is the conversion of an object from one data type to another data type.
2. Implicit Type Conversion is automatically performed by the Python interpreter.
3. Python avoids the loss of data in Implicit Type Conversion.
4. Explicit Type Conversion is also called Type Casting, the data types of objects are converted using predefined functions by the user.
5. In Type Casting, loss of data may occur as we enforce the object to a specific data type.

Thank you for reading Python Type Conversion and Type Casting.

Python Type Conversion and Type Casting

The article was published on November 15, 2020 @ 11:50 AM