In this article, you’ll learn how to explain the range function in Python. Before we get started, if you want to conditional statements in python, please go through the following article: Define Functions in Python.

One of Python’s built-in immutable sequence types is `range()`

. This function is extensively used in loops to control the number of types of loops that have to run. In simple words range is used to generate a sequence between the given values.

The `range()`

function can take 1 to 3 of the following arguments:

**Start:**The integer value for the origin of the sequence, if not passed implicitly it’s 0**Stop:**The integer value up to which the`sequence will get generated`

but won’t include this number. This is a required argument that must be passed,**Step:**Establishes the difference between each iteration it can be positive or negative if not given the default step is 1

The order of arguments is as follows, `range(start, stop, step)`

. Note that all parameters must be integers however they can be positive or negative.

**Using Range** Function** In Python**

Let’s start with generating a simple series and printing it out

1 2 3 4 | for i in range(0, 6, 1): print(i) |

Above for loop will print every number from 0 to 5 maintaining a constant difference 1. Output:

1 2 3 4 5 6 7 8 | 0 1 2 3 4 5 |

It’s worth mentioning that similar to list indexing in range starts from 0 which means `range(j)`

will print the sequence till `(j-1)`

hence the output doesn’t include 6. As mentioned earlier the default value of start is 0 and for step, it’s 1, therefore the below code produces the same output.

1 2 3 4 | for i in range(6): print(i) |

Output:

1 2 3 4 5 6 7 8 | 0 1 2 3 4 5 |

Generating a decreasing sequence is also possible by specifying a negative value to step argument.

1 2 3 4 | for i in range(30,0,-5): print(i) |

Output:

1 2 3 4 5 6 7 8 | 30 25 20 15 10 5 |

The range function can also be used to iterate over the elements of a list.

1 2 3 4 5 | li = ["1", "text", "2", "more Text",3,4,5] for i in range(len(li)): print(li[i]) |

Output:

1 2 3 4 5 6 7 8 9 | 1 text 2 more Text 3 4 5 |

It’s worth noting that in Python 2 the output of the range function was a list but in python 3 the `range()`

function doesn’t produce a list so we can’t perform list operation on it, but converting the output to a list is possible using the built-in `list()`

method.

1 2 3 4 5 6 | >>> x = list(range(6)) >>> x [0, 1, 2, 3, 4, 5] |

###### Python’s Range Function Explained

The article was published on October 3, 2020 @ 4:11 PM

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