Type Casting

Beginning Python Programming

Makzan, 2020 April.

Type Casting

Converting between string and integer
Converting between List and Set

When to convert type?

Inputs are always string, we need to convert numeric input into integer.
Data fetching from the web may be string but we need integer or float type.
We need string representation of the data
We need to convert between collection types, such as list to set.

Converting String ⮂ Integer

age = input("What is your age? ")
age = int(age)
print(type(age))

# Result:
> What is your age? 32
> <class 'int'>

Converting List ⮂ Set

L = [1,2,3,3,3,4,5]
S = set(L)
print(S)
print(list(S))

# Result:
> {1, 2, 3, 4, 5}
> [1, 2, 3, 4, 5]

Type Casting

Summary

# Convert to int
int('123')
int(123.0)

# Convert to float
float('123.4')
float(123)

# Convert to string
str(123)

# Convert to list
list({1,2,3,4})

# Convert to set
set([1,2,3,3,3])