18.05 | Spring 2022 | Undergraduate

# Introduction to Probability and Statistics

## R Tutorial: Functions

### Time

We estimate this tutorial will take 10 minutes. It consists of two simple examples of writing functions.

# R has many built in functions like `sin(x), exp(x), print(s)`. Generally speaking, you won’t write functions on the command line. Rather, they will be put in source files, or in the source pane in R Studio.
# Here we will give two simple examples of writing our own function.

# You should paste this code into the source window and then choose ‘Source’ under the ‘Code’ menu. Then practice

#Here’s a simple function that squares its argument.

``````square_me = function(n) {
x = n*n
return(x)
}
``````

# Now you can call this function from the command line

``````> square_me(4)
[1] 16
``````

Here’s a function that builds and prints a phrase from some input strings.

``````hello_there = function(name, adjective) {
phrase = paste("Hello ", name, "! You look ",
print(phrase)
}
> hello_there("Jerry", "fuzzy")
[1] "Hello Jerry ! You look fuzzy ."
``````

## Course Info

Spring 2022
##### Learning Resource Types
Lecture Notes
Problem Sets with Solutions
Exams with Solutions