Lab 2: A Simple Program

Expressions

What are they?

An expression is just a fancy name for something that can be "turned" or evaluated to a single value. One of the best examples of this is a mathematical expression like "1 + 2 * 5" which can be evaluated or "turned" into the single value of 11.

How do I use them?

For now, expressions are mostly used for mathematical equations. If we want to find the addition of two numbers in Python we would write something like

sum1 = 4 + 5

4 + 5 evaluates to 9 which was stored in the variable sum1. Now if were to print sum1 it would simply display 9.

We could also have done something like this

num1 = 4
num2 = 5
sum1 = num1 + num2

Even though we used the variables num1 and num2 to represent the numbers 4 and 5, sum1 will still evaluate to 9.

Here is a list of python operators:

1. Division: /
2. Mulitplicattion: *
3. Addition: +
4. Subtraction: -
5. Modulus: %