Nested Lists & String Formatting

 

A list as an item of another list.

Accessing Nested List

Code

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list_a = [5, "Six", [8, 6], 8.2]

print(list_a[2])

PYTHON

Output

[8, 6]

Accessing Items of Nested List

Example - 1

Code

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list_a = [5, "Six", [8, 6], 8.2]

print(list_a[2][0])

PYTHON

Output

8

Example - 2

Code

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list_a = ["Five", "Six"]

print(list_a[0][1])

PYTHON

Output

i

String Formatting

Code

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name = input()

age = int(input())

msg = ("Hi " + name + ". You are "+ str(age) + " years old.")

print(msg)

PYTHON

String formatting simplifies this concatenation.

It increases the readability of code and type conversion is not required.

Add Placeholders

Add placeholders

{}

where the string needs to be formatted.

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msg = "Hi {}. You are {} years old."

msg.format(val_1, val_2,..)

PYTHON

Inserts values inside the string’s placeholder

{}

Code

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name = "Raju"

age = 10

msg = "Hi {}. You are {} years old."

print(msg.format(name, age))

PYTHON

Output

Hi Raju. You are 10 years old.

Number of Placeholders

Code

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name = "Raju"

age = 10

msg = "Hi {}. You are {} years old {}."

print(msg.format(name, age))

PYTHON

Output

IndexError: Replacement index 2 out of range for positional args tuple

Numbering Placeholders

Numbering placeholders, will fill values according to the position of arguments.

Code

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name = input()

age = int(input())

msg = "Hi {0}. You are {1} years old."

print(msg.format(name, age))

PYTHON

Input

Raju

10

Output

Hi Raju. You are 10 years old.

Code

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name = input()

age = int(input())

msg = "Hi {1}. You are {0} years old."

print(msg.format(name, age))

PYTHON

Input

Raju

10

Output

Hi 10. You are Raju years old.

Naming Placeholder

Naming placeholders will fill values according to the keyword arguments.

Code

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name = input()

age = int(input())

msg = "Hi {name}. You are {age} years old."

print(msg.format(name=name, age=age))

PYTHON

Input

Raju

10

Output

Hi Raju. You are 10 years old.