Absolute value

Previously we fit a straight line to your run times. Now you want to examine how far the values of your run times were from the predictions of the straight-line fit. A common way to do this is by using the absolute difference between the values.

You need to write a function that can calculate the absolute values so you can perform this analysis.

The array of residuals between the straight line and your run times is available in your environment as residuals.

This exercise is part of the course

Introduction to Julia

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Exercise instructions

Begin a function named absolute(), which takes a single input value of x.
In the function's body, write an if-statement so the function will return x if x>=0 and will return -x otherwise.
Use the function to calculate and print the absolute value of each element of the residuals array.

Hands-on interactive exercise

Have a go at this exercise by completing this sample code.

# Begin the absolute function
____
	# Write an if-statement to return absolute value of x
	if ____
    	____
    else
    	____
    end
end

# Use the function on residuals
println(____(____))

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