7.2. Defining Functions - How¶
The same syntax we use to name procedures can be used to define new functions. The only difference
is that a function will return a value. To return a value from a function use the Python
keyword return followed by the value to return. The value can be a literal value like 3.14
or "Hello there", but will generally be a variable that we calculated within the function.
This is a definition for a function that accepts the lengths of the two legs (shorter sides) of a
right triangle as its parameters and calculates the length of the hypotenuse (long side). The final
value that it computes - sideC is what gets returned.
Of course, running it right now does nothing. Just like a procedure definition, a function definition
does not cause anything to happen on its own. It is only the instructions for what to do when
someone calls hypotenuse_length. So let’s add a call to the function. This working program
asks for the lengths of two sides from the user and then uses those two values a and b to
call hypotenuse_length.
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