Functions
SDS 192: Introduction to Data Science
Lindsay Poirier
Statistical & Data Sciences, Smith College
Fall 2022
For Today
- Quiz 2 Posted!
- Don’t forget about the Study Plan Assessment
- Writing Functions
- Code Along
Why write functions?
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Why write functions?
- Reduces the amount of code to write
- Lowers the chances of errors in code
- Supports reproducibility
Functions
- Statements organized to perform a specific task
- Take arguments as inputs
- Arguments can be required or optional
- Return a value or set of values as outputs
- Default value is output of last line of function if not specified
User-defined Functions
Calling Functions
- This is the same way you’d call functions built-in to
R
User-defined Functions
state_nameis a required argument here.
Making Arguments Optional
- Because we provide a deafult value for year, it is optional in the function call.
Naming Arguments
- Naming helps to differentiate between arguments. Order matters if arguments aren’t named!
Functions SDS 192: Introduction to Data Science Lindsay Poirier Statistical & Data Sciences , Smith College Fall 2022