Defining a custom function

Intermediate Python for Developers

George Boorman

Curriculum Manager, DataCamp

Calculating the average

# Sales variable
sales = [125.97, 84.32, 99.78, 154.21, 78.50, 83.67, 111.13]


# Calculating average sales
average_sales = sum(sales) / len(sales)


# Rounding the results
rounded_average_sales = round(average_sales, 2)
print(rounded_average_sales)

105.37

Create a custom function

Considerations for making a custom function:
- Number of lines
- Code complexity
- Frequency of use
- Don't Repeat Yourself (DRY)

Desert

Creating a custom function

# Create a custom function to calculate the average value
def

Creating a custom function

# Create a custom function to calculate the average value
def average

Creating a custom function

# Create a custom function to calculate the average value
def average(

Creating a custom function

# Create a custom function to calculate the average value
def average(values)

Creating a custom function

# Create a custom function to calculate the average value
def average(values):

Creating a custom function

# Create a custom function to calculate the average value
def average(values):
    # Calculate the average
    average_value = sum(values) / len(values)

Creating a custom function

# Create a custom function to calculate the average value
def average(values):
    # Calculate the average
    average_value = sum(values) / len(values)

    # Round the results
    rounded_average = round(average_value, 2)

Creating a custom function

# Create a custom function to calculate the average value
def average(values):
    # Calculate the average
    average_value = sum(values) / len(values)

    # Round the results
    rounded_average = round(average_value, 2)


    # Return an output
    return

Creating a custom function

# Create a custom function to calculate the average value
def average(values):
    # Calculate the average
    average_value = sum(values) / len(values)

    # Round the results
    rounded_average = round(average_value, 2)

    # Return rounded_average as an output
    return rounded_average

Returning a calculation

# Create a custom function to calculate the average value
def average(values):
    # Calculate the average
    average_value = sum(values) / len(values)

    # Return the rounded results
    return round(average_value, 2)

Using a custom function

sales = [125.97, 84.32, 99.78, 154.21, 78.50, 83.67, 111.13]


# Calculating the average
average(sales)

105.37

Storing a function's output

# Calculating the average
average(sales)

105.37

# Storing average_sales
average_sales = average(sales)

print(average_sales)

105.37

Let's practice!

Intermediate Python for Developers