Naming your package

available::available("mypackage")

Creating your package

File > New Project > New Directory > R Package

Package directory

• R where R scripts for functions are stored.
• man where documentation files are stored.
• DESCRIPTION contains the metadata about the package.
• NAMESPACE will be generated automatically. More on this later.

More components to follow later (e.g. data storage).

Shortcuts

Install Package: Cmd + Shift + B Check Package: Cmd + Shift + E Test Package: Cmd + Shift + T

Adding a license

usethis::use_mit_license("Mine Dogucu")

✓ Writing 'LICENSE' # what CRAN requires
✓ Writing 'LICENSE.md' # created only for human-readers
✓ Adding '^LICENSE\\.md$' to '.Rbuildignore' # LICENSE.md is ignored when package is built

usethis license functions

Writing functions

• Functions are written in an .R file and stored in the R file.

• You do not need one .R file per function. If functions are closely related you may want to keep them in a single file.

Documenting functions

When your cursor is inside a function code, then click on Code>Insert ROxygen Skeleton

#' Mean and Median Summaries for Numerical Vectors
#'
#' @param some_variable a numeric vector
#' @param na.rm indicates whether missing data should be removed or not
#' #' @return a numeric vector with mean and median values
#' @export
#' @importFrom stats median dbinom
#' @examples
#' print_mean_median(mtcars$mpg, na.rm = TRUE)

Dependencies

• All functions that are from packages other than base need to be explicitly imported, either as a function or as a full package.

• All functions from a package can be imported with @import

• Specific functions can be imported with @importFrom stats median dbinom

Documentation

devtools::document()

Workflow so far

1. Write function
2. Add ROxygen Skeleton and write documentation
3. devtools:document()
4. devtools:check()

Testing

devtools::test()
x No testing infrastructure found. Create it?
1: Yes
2: No

This will create the tests folder where we will store the previously written tests. We will use the tests from last week.

Workflow

1. Write function
2. Add ROxygen Skeleton and write documentation
3. devtools:document()
4. devtools:check()
5. Write tests
6. devtools:test()