You know, those fancy functions that make your code look all sophisticated and stuff?
First off, let’s start with the good: round(). This method is a lifesaver when you need to round numbers. It takes one argument, which is the number you want to round, and returns an integer or float depending on whether you specify the second argument as True or False (respectively). For example:
# Define a variable x and assign it the value of pi
x = 3.141592653589793
# Use the round() method to round x to the nearest integer and assign it to variable y
y = round(x)
# Print the value of y
print(y) # prints 3
# Use the round() method again, this time specifying the second argument as True to return a float
z = round(x, True)
# Print the value of z
print(z) # prints 3.1
Now that we’ve covered the good, let’s move on to the bad: math.floor(). This method is similar to round(), but it always rounds down instead of up or towards zero (depending on whether you specify a second argument). While this may seem like a minor difference, it can actually cause some issues if you’re not careful. For example:
# The math.floor() method is used to round a number down to the nearest integer.
# It takes in two arguments, the number to be rounded and a boolean value indicating whether to round towards zero or not.
x = 3.141592653589793 # Assigning a float value to the variable x
y = math.floor(x) # Rounding x down to the nearest integer and assigning it to the variable y
print(y) # Printing the value of y, which is 3
z = math.floor(x, True) # Rounding x down to the nearest integer, but specifying to round towards zero
print(z) # Printing the value of z, which is still 3 because the second argument is ignored when using math.floor()
Wait a minute… didn’t we just say that the second argument specifies whether to round up or not? Well, apparently not for math.floor(). This can be confusing and lead to errors in your code if you’re not careful. So, beware!
Finally, the ugly: int(). This method is used to convert a number (or string) into an integer. While this may seem like a simple task, it can actually cause some issues depending on how you use it. For example:
# This script demonstrates the use of the int() method to convert a string into an integer.
# First, we assign the string "3" to the variable x.
x = "3"
# Then, we use the int() method to convert x into an integer and assign it to the variable y.
y = int(x)
# We print the value of y, which should be 3.
print(y) # prints 3
# Next, we try to convert the string "3.14" into an integer and assign it to the variable z.
# However, since "3.14" is not a whole number, the int() method throws a ValueError.
z = int("3.14")
# We print the value of z, but this line will not be executed due to the error in the previous line.
print(z) # throws a ValueError!
Wait, what? Why did it throw an error for the second example? Well, that’s because we tried to convert a string with a decimal point into an integer. This is not allowed in Python (unless you use int() with a second argument). So, be careful when using this method!