Unlike the previous guide, we're going to use a Python shell to run the commands. A shell is simply an interface for accessing some service, in this case Python.
Python ships with a shell by default. To open the Python shell, use the following:
You should shell a Python prompt that looks something like this:
Python 3.6.5 (default, Mar 30 2018, 06:41:53) [GCC 4.2.1 Compatible Apple LLVM 9.0.0 (clang-900.0.39.2)] on darwin Type "help", "copyright", "credits" or "license" for more information. >>>
Here are the operators we'll cover in this guide:
|+||Addition||Add two numbers.||2 + 2|
|-||Subtraction||Subtract a number from another.||2 - 1|
|*||Multiplication||Multiply two numbers.||2 * 2|
|/||Division||Divide a number by another.||2 / 2|
|%||Modulus||Get the remainer of the left hand operand divided by the right hand operand.||10 % 3|
|**||Exponent||Performs exponential power operations.||2 ** 3|
|//||Floor Division||Division with the decimal point removed.||3 // 2|
Each of these operators will be covered in the following steps. To gain familiarity with the Python shell as well as arithmetic operators, open a Python shell and practice using each operator.
Chances are, you've encountered this one before. In case you haven't, it's the process of finding the sum of two or more numbers.
>>> 2 + 2 4
>>> 100 - 30 70
>>> 10 * 3 30
>>> 40 / 10 4.0
Notice here that the result is not
4.0. Python 3 uses true division (as opposed to Python 2, which uses floor division). This means the result will always be a floating point number representing the fractional result. See the different:
>>> 1 / 2 0
>>> 1 / 2 0.5
Related to the division operator, this operator gives us the remainder of a division operation.
>>> 10 % 3 1
>>> 2 ** 8 256
This operator gives us what we expect from the division operator in Python 2. It performs the division operation and returns an integer, chopping off any trailing decimals.
>>> 10 // 3 3