Section 5.3 Type conversion functions
Python also provides built-in functions that convert values from one type to another. The int function takes any value and converts it to an integer, if it can, or complains otherwise:
Checkpoint 5.3.1.
Q-2: Why would we get an error in the following code block?
print(int('32'))
print(int('Hello'))
When converting a string to an int, we must remove the quotation marks.
Incorrect! This would only work if Hello was a variable name with a value of the correct type. For example, Hello = '32'. Try again.
The int function is expecting a value that can be converted to an integer.
Correct! The int function expects a value that can be converted and strings cannot be converted to integers.
We cannot print and call a function in the same line.
Incorrect! This is actually possible — it worked with the first line. Try again.
int can convert floating-point values to integers, but it doesn't round them — it chops off the fraction part (this is called “truncating”):
float converts integers and strings to floating-point numbers:
Finally, str converts its argument to a string:
Checkpoint 5.3.2.
Checkpoint 5.3.3.
Q-7: Consider the code below. What prints?
23
Correct! The int function will truncate the float when it converts it to an integer.
24
Incorrect! The int function doesn't round up. Try again.
2
Incorrect! The int function doesn't only convert the first digit. Try again.
23.8
Incorrect! The int function doesn't keep any of the decimal places. Try again.
Checkpoint 5.3.4.
Q-8: Consider the code below. What prints?
24.0
Incorrect! The float function will be the same value as the integer. Try again.
2.3
Incorrect! The float function will not split a multi-digit integer. Try again.
23.0
The float function will add ".0" to the end of an integer, turning it into a floating point number.
23
Incorrect! Floating point numbers have a decimal point in them. Try again.
