# The Python range() Method

The python `range()` function creates a list of integers, typically used in the for loop.

syntax of range function

``````range(start, stop[,step])
``````

Parameter description:

• start:Count from start, default from 0
• Stop:Count to the end of the stop, but not the stop.
• step:step length, default is 1.

Related course: Complete Python Programming Course & Exercises

## Range Example

### With one parameter

The programs below demonstrate usage of `range()`. The sequence ends with stop-1, where the parameter is stop.

``````range(10)
[0,1,2,3,4,5,6,7,8,9]
range(1,11)
[1,2,3,4,5,6,7,8,9,10]
range(0,30,5)
[0,5,10,15,20,25]
range(0,-10,-1)
[0,-1,-2,-3,-4,-5,-6,-7,-8,-9]
range(0)
[]
range(1,0)
[]
``````

range can also be used in for, looping out each letter of the word

``````x='python'
for i in range(len(x)):
print(x[i])
``````

Only one parameter, representing all integers from 0 to this parameter, excluding the parameter

``````ran=range(10)
#define a list, which is used to age all the numbers in the range of the range as a list
arr_str=list(ran)
print(ran)
print(arr_str)
``````

This outputs:

``````>>> ran=range(10)
>>> arr_str=list(ran)
>>> print(ran)
range(0, 10)
>>> print(arr_str)
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>>
``````

### With two parameters

Two arguments, the first for the left boundary, the second for the right boundary, and the range for all integers from the left boundary to the right boundary, left closed and right open.

``````ran=range(1,15)
arr_str=list(ran)
print(ran)
print(arr_str)
``````

Outputs:

``````>>> ran=range(1,15)
>>> arr_str=list(ran)
>>> print(ran)
range(1, 15)
>>> print(arr_str)
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14]
>>>
``````

### With three parameters

Three parameters, the first representing the left boundary, the second representing the right boundary, and the third representing the step step, i.e. the difference between two integers, left closed and right open.

``````ran=range(1,15,2)
arr_str=list(ran)
print(ran)
print(arr_str)
``````

Outputs:

``````>>> ran=range(1,15,2)
>>> arr_str=list(ran)
>>> print(ran)
range(1, 15, 2)
>>> print(arr_str)
[1, 3, 5, 7, 9, 11, 13]
>>>
``````