Summary  
This chapter explains how to convert numerical values between types in Python, demonstrating the use of functions like int() to cast floats, scientific notation numbers, and numeric strings into integers.  

General domain of usage  
Data processing

At times, Python may automatically assign a data type to a variable, which might not align with our intended choice. Hence, it is advantageous to possess the capability to exert control over the data type selection.

For instance, we can turn a number into a string, change the type of numerical data, or even use whichever number as a boolean data type. In this chapter, we are going to take care of converting numerical data types.

First and foremost, take a look at the syntax of **converting a number to the integer data type**: 

value1 = int(657.89)
value2 = int(90e3)
value3 = int("678")

print(value1)
print(value2)
print(value3)

> Note
>
> It has a simple syntax, `int(number)`, but if we want to convert a string to an integer, this string should contain **integer** numbers in quotes, like `int("8990")`, not `int("899.0")`. 

import unittest


class ExpectedType:
    def __init__(self, expected_type, name):
        self.expected_type = expected_type
        self.name = name


class TestUserCode(unittest.TestCase):
    def _test_variable_equals(self, var_name, expected, expected_type=None):
        import user_code
        if not hasattr(user_code, var_name):
            return (False, f"Expected variable '{var_name}' to be defined.")
        var = getattr(user_code, var_name)

        if expected_type is not None and not isinstance(var, expected_type.expected_type):
            return (False, f"Expected '{var_name}' to be of type '{expected_type.name}', but got '{type(var).__name__}'.")

        if var != expected:
            return (False, f"Expected '{var_name}' to equal '{expected}', but got '{var}'.")
        return (True, f"The variable `{var_name}` equals '{expected}'")

    def test_integer1(self):
        passed, result_text = self._test_variable_equals(
            'integer1', 6, expected_type=ExpectedType(int, 'int'))
        self._testMethodName = result_text
        self.assertTrue(passed, result_text)

    def test_integer2(self):
        passed, result_text = self._test_variable_equals(
            'integer2', 28, expected_type=ExpectedType(int, 'int'))
        self._testMethodName = result_text
        self.assertTrue(passed, result_text)

    def test_integer3(self):
        passed, result_text = self._test_variable_equals(
            'integer3', 496, expected_type=ExpectedType(int, 'int'))
        self._testMethodName = result_text
        self.assertTrue(passed, result_text)


if __name__ == '__main__':
    unittest.main()

test_main.py

This course is going to help you dive deeper into data types and try to work with them. Here you will learn basic operations and all ins and outs of numbers, boolean data type, and strings. This course consists of a lot of practical tasks after which you will become a skillful programmer.

Numeric data types are crucial in Python, so it is important to start with them. Here you will work with simple math operations and find out the purposes of learning different types of numerical data.

Mastering boolean data types and logical operations in Python. You'll learn how to work with True and False, apply logical operators like and, or, and not, and understand how operator precedence works in complex expressions.

Strings are an essential part of Python programming, allowing you to work with text data. In this section, you'll learn how to manipulate strings, extract characters, slice words, and search for specific phrases.

This chapter consists of practical tasks that combine all the examined topics together with a bit of theory.

Convert Types

Solution

Awesome!

Convert Types

Solution

Awesome!