4️⃣

2.4 Casting

Casting

However, you can change strings into integers or floating numbers, but only if they’re numbers already. If you want x = ‘5’ to be x = 5, you can say int(x) or float(x), but the float turns it into 5.0. But this method only works if your variable is a number. If it has any letters in it at all, then trying to turn it into an integer or float will give you an error.

x = '5'
y = '6'
sum = int(x) + int(y)
# this is 11 because x and y were converted to integers
print(sum)

a = 5
message = "Hello!"
a = str(a)
# converts to string so that concatenation works
print(message + " " + a)

View code on GitHub.

💡

Note: If you want to know the type of a variable, you can use the type() function. For example:

# print the type of a variable
a = 5
print(type(a)) # prints the <class 'int'>

View code on GitHub.

Practice

Int

Set a variable x to “12” and turn it into an integer. Print the result.

Float

Write a program that takes a number from the user and stores it in a variable. Cast the number to an integer and store in another variable. Then print: (floating point number) = (integer). Also print the type of the floating point variable. Remember! type(variable_name) will return the data type of a variable.

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