Mathematical utilities
Have another look at some useful math functions that R features:
abs()
: Calculate the absolute value.sum()
: Calculate the sum of all the values in a data structure.mean()
: Calculate the arithmetic mean.round()
: Round the values to 0 decimal places by default. Try out?round
in the console for variations ofround()
and ways to change the number of digits to round to.
As a data scientist in training, you've estimated a regression model on the sales data for the past six months. After evaluating your model, you see that the training error of your model is quite regular, showing both positive and negative values. A vector errors
containing the error values has been pre-defined for you.
This exercise is part of the course
Intermediate R
Exercise instructions
Calculate the sum of the absolute rounded values of the training errors. You can work in parts, or with a single one-liner. There's no need to store the result in a variable, just have R print it.
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
# The errors vector has already been defined for you
errors <- c(1.9, -2.6, 4.0, -9.5, -3.4, 7.3)
# Sum of absolute rounded values of errors