Belajar Python [Dasar] - 06 - Casting Tipe Data

Summary

In this Python tutorial, the instructor explains the concept of type casting, which involves converting one data type into another. They demonstrate how to cast integers, floats, strings, and booleans, providing examples for each. The tutorial covers how each type behaves when converted, such as rounding down a float to an integer or converting a string to a boolean based on its content. By the end, viewers learn the different behaviors of casting in Python, and the tutorial concludes with a preview of upcoming lessons on user input handling.

Takeaways

• 😀 Casting in Python refers to converting one data type into another (e.g., integer to string, float to boolean).
• 😀 Data types in Python that can be casted include integer, float, string, and boolean.
• 😀 To cast a data type, you can use specific functions like `int()`, `float()`, `str()`, and `bool()`.
• 😀 An example of casting: converting an integer `9` to a string with `str(9)` results in `'9'`.
• 😀 You can convert a float like `9.5` to an integer, but this will truncate the decimal part, as shown by casting `9.5` to `int()` resulting in `9`.
• 😀 A `bool()` function will return `False` when the value is `0` or an empty value and `True` for any non-zero or non-empty value.
• 😀 When converting from a float like `9.5` to an integer, it will round down to the nearest whole number (e.g., `9.5` becomes `9`).
• 😀 Casting from a non-numeric string to an integer or float will result in an error unless the string represents a valid number.
• 😀 A boolean value can be derived from an integer or float where `0` and `0.0` are considered `False`, and any non-zero value is `True`.
• 😀 When casting a string to a boolean, an empty string is considered `False`, while any non-empty string is considered `True`.
• 😀 Python requires proper syntax when casting; for example, you cannot cast a non-numeric string directly to an integer without causing an error.

Q & A

What is the main purpose of data type casting in Python?

Data type casting in Python is used to convert one data type into another. This allows different types of data, such as integers, strings, and floats, to be handled and manipulated appropriately in various operations.

How can you cast an integer to a float in Python?

To cast an integer to a float, you can use the 'float()' function. For example, 'float(9)' would convert the integer 9 to the float 9.0.

What happens when you cast a float value like 9.5 to an integer?

When casting a float like 9.5 to an integer, Python truncates the decimal part and converts it to the integer part. For example, 'int(9.5)' results in 9.

What is the result of casting a string containing '9' to an integer?

If you try to cast a string containing a number, like '9', to an integer using 'int()', it will successfully convert to the integer 9. However, casting a non-numeric string will raise an error.

What is the output when you cast a boolean value, like False, to an integer?

When casting a boolean value like False to an integer, the result is 0. Conversely, True would be cast to 1.

Can you cast a non-numeric string, such as 'apple', into an integer or float?

No, you cannot directly cast a non-numeric string, like 'apple', to an integer or float. Trying to do so will result in a ValueError.

What does casting a float to a boolean result in?

When you cast a float to a boolean, any non-zero float value will be considered True, and a float value of 0.0 will be considered False.

What happens when you try to cast a non-numeric string to a float?

If you attempt to cast a non-numeric string (like 'hello') to a float, Python will raise a ValueError because it cannot interpret the string as a valid float.

How do you cast a string with numeric characters, like '10', into a boolean?

If you try to cast a string containing numeric characters like '10' into a boolean, it will be converted to True because non-empty strings are considered True in Python.

What is the effect of casting an empty string ('') to a boolean?

When you cast an empty string ('') to a boolean, the result will be False. In Python, an empty string is considered a falsy value.