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3.3 USE OF "RANGE()" FUNCTION
Python supports a variety of functions which make it very rich in doing the complex things
very easily. One such function is “range()”.

“range()” function is used to generate a sequence of set of values starting from a particular
number called lower limit to another number called upper limit. A sequence is the occurrence
of values in a linear order. It works on integer or numeric values only.
Let us now see how the range() function works. Its syntax is:

range(<lower-limit>, <upper-limit>)

The range(1,n) function will generate a sequence of values from 1 to n-1 with an increasing
value(called Step-value) of 1 by default.
Some few examples are:

Statement Sequence of values generated Step Value or Increasing Value
range(0, 5) [0,1,2,3,4] 1
range(10,17) [10,11,12,13,14,15,16] 1

range(4,9) [4,5,6,7,8] 1
1 (as the lower limit is greater than the
range(8,0) Blank [ ]
upper limit)

APPLICATION OF “RANGE()” FUNCTION WITH SKIP VALUES
As we have discussed above, “range()” function is used to generate a sequence of values
starting from a particular number called lower limit to another number called upper limit
with a DEFAULT SKIP VALUE of 1. Here, Skip value means the next value which comes

after one value, then 2 value, and so on.
nd
But in this section, we shall discuss that this default skip value may be changed and
therefore, its output result. We may pass a Skip value in the range() function that will skip
that much value in the previous value and generate a new value till the upper-limit.

In the statement range(1,n,2), one will get a sequence of values (1, 3, 5, … up to n - 1).

We can better understand this by using the following example:
Statement Sequence of values generated Step/Skip Value

range(0, 5, 2) [0,2,4] 2
range(10,17, 3) [10,13,16] 3
range(4,9, 2) [4,6,8] 2
range(8,0, -1) [8,7,6,5,4,3,2,1] -1
range(8,0, -2) [8,6,4,2] -2

range(8,0, -3) [8,5,2] -3

The main application of the range() function will come along with ‘for’ loop which will be
discussed in the next section with plenty of examples.

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