a = 10
b = -5
c = 0
print(a, b, c)10 -5 0Number Types in Python
This notebook introduces Python’s built-in number-related types: integers, floats, and complex numbers, along with type conversion, type checking, and small exercises.
Integers (int)
Integers are whole numbers (positive, negative, or zero) without decimal points.
Examples:
Exercise: Create two integer variables and print their sum.
x = 7
y = 12
print("Sum:", x + y)Sum: 19Floating Point Numbers (float)
Floats are numbers with decimal points or in scientific notation.
Examples:
pi = 3.14159
tax_rate = 0.07
distance = -2.5
avogadro = 6.022e23
print(pi, tax_rate, distance, avogadro)3.14159 0.07 -2.5 6.022e+23Exercise: Create a float variable for temperature and print it in a sentence using an f-string.
temperature = 23.5
print(f"The current temperature is {temperature}°C.")The current temperature is 23.5°C.Complex Numbers (complex)
Complex numbers have a real and imaginary part, written as a + bj.
Examples:
z1 = 2 + 3j
z2 = 1 - 4j
print("z1:", z1)
print("z2:", z2)
print("Sum:", z1 + z2)z1: (2+3j)
z2: (1-4j)
Sum: (3-1j)Why Use j for Complex Numbers in Python?
In mathematics, the imaginary unit is often written as i. However, in engineering, i is commonly used to represent electric current. To avoid confusion, Python uses j to represent the imaginary unit (√-1).
Example: - 1j means the imaginary number 0 + 1×j. - 2 + 3j means a complex number with real part 2 and imaginary part 3.
# Complex number example with j
z = 2 + 3j
print(z) # prints 2 + 3j
# Accessing real and imaginary parts
print("Real part:", z.real)
print("Imaginary part:", z.imag)(2+3j)
Real part: 2.0
Imaginary part: 3.0Exercise: Create two complex numbers and multiply them.
z1 = 2 + 3j
z2 = 1 - 4j
result = z1 * z2
print("Multiplication result:", result)Multiplication result: (14-5j)Type Conversions
Convert between number types using int(), float(), and complex().
print(int(3.7))
print(float(5))
print(complex(2, 3))3
5.0
(2+3j)Exercise: Convert an integer to a float and a float to an integer, then print the results.
my_int = 10
my_float = 5.99
converted_to_float = float(my_int)
converted_to_int = int(my_float)
print("Integer to float:", converted_to_float)
print("Float to integer:", converted_to_int)Integer to float: 10.0
Float to integer: 5Checking Types
print(type(10))
print(type(3.14))
print(type(2+3j))<class 'int'>
<class 'float'>
<class 'complex'>Exercise: Use type() to check the type of a number you define.
value = 42.0
print(type(value))<class 'float'>Common Pitfalls
print(0.1 + 0.2 == 0.3) # Floating-point precision issue
print(5 / 2) # Division returns float
print(5 // 2) # Floor division returns intFalse
2.5
2