# Tuples¶

List is an immutable collection of elements(may be of same or different types), which is indexed by a 0-based integer. A 2-tuple can represent a point in 2-D plane, or a 3-Tuple can represent a point in 3-D plane.

## Creating Tuple¶

- Creating an empty tuple

```
x = () # () denotes a tuple type
# or
x = tuple()
```

- Creating list with some initial elements

```
x = (2,3,0,'g')
```

```
In [1]:
```

```
x = (2,3)
```

```
In [2]:
```

```
x
```

```
Out[2]:
```

```
(2, 3)
```

```
In [3]:
```

```
x = (2,) # x = (2) assigns int 2 to x. To make it a tuple, a comma is appended
```

```
In [4]:
```

```
x
```

```
Out[4]:
```

```
(2,)
```

```
In [5]:
```

```
x + (1,2)
```

```
Out[5]:
```

```
(2, 1, 2)
```

Tuples are immutable. So once a tuple is created, its contents are permanent unless it is reassigned with another tuple.

Tuples can also be Indexed and Sliced like lists

```
In [6]:
```

```
x
```

```
Out[6]:
```

```
(2,)
```

```
In [7]:
```

```
x = x + (1,3,4) # Reassignment
```

```
In [8]:
```

```
x
```

```
Out[8]:
```

```
(2, 1, 3, 4)
```

```
In [9]:
```

```
x[1]
```

```
Out[9]:
```

```
1
```

```
In [12]:
```

```
x[2:5]
```

```
Out[12]:
```

```
(3, 4)
```

```
In [13]:
```

```
x[::-1]
```

```
Out[13]:
```

```
(4, 3, 1, 2)
```

## Operations on Tuples¶

Since tuples are immutable, operations do not modify the original tuple

Here are some of the operations on list. They are member functions of
`class tuple`

. If `x`

is a tuple,

`x.index(ele)`

- searches for the given element from the start of the list and returns its index. Throws a`ValueError`

if the element does not appear (use`in`

to check without a ValueError).`x.count(ele)`

- counts the number of occurances of`ele`

in`x`

Membership operator `in`

is also supported

```
In [14]:
```

```
x
```

```
Out[14]:
```

```
(2, 1, 3, 4)
```

```
In [15]:
```

```
2 in x
```

```
Out[15]:
```

```
True
```

```
In [16]:
```

```
x.count(2)
```

```
Out[16]:
```

```
1
```

```
In [17]:
```

```
x.index(3)
```

```
Out[17]:
```

```
2
```

Using a list of tuples, one can model a collection of points in space