# Learning Python: Lists And Tuples.


# LIST

## What is list?

List is a collection of data enclosed by []. Lists are mutable , which means the values inside the list can be changed anytime . List may contain string , integers ,a list inside a list or all of these in a single list itself.

A list can be created by simply putting values enclosed by [].

## List operations.

### 1. Length of a list .

To know the length of  list we use len() function. for ex.

``` python
list1=[1,2,3]
len(list) #this will return 3 
```

### 2. Indexing in list.

Elements of a list are arranged in a definite sequence ,called indexes . The first element is treated as (0)th index and last element is treated as (n-1)th index . for ex.

``` python
list1=[10,20,30]
#index of 10 is 0
#index of 20 is 1 
#index of 30 is 2
```

### 3. Slicing in ist.

Slicing is sublist of a list. for ex.

``` python
list1=[1,2,3,4,5]
list2=list1[1:3] #this will extract a new list from index 1 to 3 .
print(list2) #output will be [2,3] as 3 gets excluded.
```

### 4. Adding and removing elements in a list.

a. We can add an element in a list by using append() fucntion .

Append fuction will add an element to a list at the end .Append will only insert 1 element ,to add multiple elements we use insert() fuction.

``` python
list1=[1,2,3]
list1.append(4)
#this will add 4 at the end of list1  
#new list is [1,2,3,4]
```

b. insert fuction

``` python
list1=[1,2,3]
list1.insert(4,5,6)
#this will add 4,5,6 at the end of list1
#new list is [1,2,3,4,5,6]
```

c. To merge two lists extend fucion is used. for ex,

``` python
list1=[1,2,3]
list2=[4,5,6]
list1.extend(list2)
#this will merge the two lists and return [1,2,3,4,5,6]
```

d.To remove an element in a list we use pop() fuction.

pop function will remove the indexed element and return it to the user. for ex.

``` python
list1=[1,2,3,4]
list1.pop(3) #this will remove the 4th elements i.e 4 from the list as at 3rd index 4 is there.
```

e. To remove elements we use remove function. remove fuction will remove the element given by the user . for ex.

``` python 
list1=[2,3,4,5,6]
list1.remove(5)
#this will remove 5 from the list
```

f. Sorting :- sort() fucntion will arrange the elements of the list in ascending order .

``` python
list1=[4,3,2,6,1]
list1.sort()
#this will sort the list and return [1,2,3,4,6]
```

### *HERE IS CODE HAVING MULTIPLE OPERATIONS OF A LIST*.

``` python
x='hello'
list1=[20,12,32,11,65,32]
print(list(x)) #create a list of alphabets 'hello'
print(list1.append(13)) #this will add 13 to the list.
list2=list1[2:5] #slicing
print(list2) #this will create a new list having 3 elements only.
print(list1.sort()) # this will sort the list in ascending order.
print(list1.reverse()) # this will reverse the list.
print(list1.extend(list2)) #this will add all the elements of list2 in list1.
x=list1.pop() # pop fucntion
print(x) #poped item
print(list1.remove(12)) # this will remove 12 from the list.
#end 
```



# TUPLES

## What is a tuple?

Tuple is  collection a data like list . The values stored in a tuple can be of any data type seperated by commas . Tuples are immutable means the values can not be changed like in list.

A tuple can be created by simply adding values enclosed by () seperated by commas .

## Tuple operations.

### 1.  creating a tuple.

``` python
x='hello'
tuple1=tuple(x)
print(tuple1)
#this will create a tuple for the word hello where each alphabet gets seperated by a comma.
```

### 2. Length of tuple .

Len function is used to find the length of a tuple. for ex.

``` python
tuple1=(1,2,34,4)
len(tuple1) #this willl return 4 (the length of tuple1.)
```

### 3. Indexing in tuple.

Indexing in tuple is same as of list .

``` python
tuple1=(1,2,3,4)
print(tuple1[2])
#this will return 3 ,as 3 is in second index.
```

### 4. Concatenation in tuples.

Two tuples can be concatenated by simply using + between them. for ex.

``` python
tuple1=(1,2,3)
tuple2=(4,5,6)
tuple3=tuple1+tuple2
print(tuple3)#merged tuple.
```

### 5. Deleting a tuple.

A tuple can be deleted by using del() function

``` python
tuple1=(1,2,3)
del tuple1 # tuple deleted
print(tuple1) #this will give error as tuple1 is already deleted.
```

### 6. Maximum and minumum value in a tuple.

By using min and max fuction we can find the minimum and maximum value in a tuple.

for ex.

``` python
tuple1=(2,4,5,6,3)
tuple1.max() # this will return 6
tuple2.max() # this will return 2
```

## *HERE IS CODE HAVING MULTIPLE OPERATIONS OF A TUPLE.*

``` python
x='hello'
tuple1=(20,12,32,11,65,32)
print(tuple1(x)) #create a tuple of alphabets 'hello'
tuple2=tuple1[2:5] #slicing
print(tuple2) #this will create a new tuple having 3 elements only.
print(tuple1[0])# this will return value at index 0.
print(tuple1.max())
del tuple1 #this will delete tuple.
#end 

```

# *DIFFERENCE BETWEEN A LIST AND A TUPLE.*



| s.no | DIFFERENCES                                                  |
| ---- | ------------------------------------------------------------ |
| 1.   | Lists are mutable whereas tuples are immutable .So we can use them according to our preferences. We can use tuple for data that need not to be changed later . |
| 2.   | Operations in tuple is bit faster than lists.                |
| 3.   | Lists provide more fuctions in comparison to tuple.          |