Ranges

Introduction:

  • To loop through a set of code a specified number of times, we can use the range() function.
  • The range() function returns a sequence of numbers, starting from 0 by default, incrementing by 1 by default, and ending at a specified number.

Syntax of range():

python
range(start, stop, step)
  • start: Optional. The starting value (default is 0).
  • stop: Required. The stopping value (not included).
  • step: Optional. The increment value (default is 1).

Defining a Range:

  • You can define a range using the boundaries: start and stop. You can also specify a step value.

  1. Range with Specific Stop:

    python
    my_range = range(9)
print(list(my_range))
    • Output: [0, 1, 2, 3, 4, 5, 6, 7, 8]
       

  2. Range with Specific Start and Stop:

    python
    my_range = range(4, 9)
print(list(my_range))
    • Output: [4, 5, 6, 7, 8]
       

  3. Range with Specific Start, Stop, and Step:

    python
    my_range = range(4, 9, 2)
print(list(my_range))
    • Output: [4, 6, 8]
       

Negative Step Value in a Range:

  • You can define a range with a negative step value when the start value is greater than the stop value.

    python
    my_range = range(9, 4, -2)
print(list(my_range))
    • Output: [9, 7, 5]
       

Printing Values in a Range:

  • To print the values in a range, convert it to a list:

    python
    my_range = range(4, 9)
print(list(my_range))
    • Output: [4, 5, 6, 7, 8]
       

Summary:

  • The range() function in Python is a powerful tool for creating sequences of numbers. Practice using the range() function to loop through sequences and understand how to define ranges with different start, stop, and step values!