Statistics and Statistical Programming (Spring 2019)/R lecture outline: Week 3
From CommunityData
Review of material from class[edit]
- loading data:
- load() versus read.csv() vs. read.delim() (w arguments like row.names=FALSE)
- when things don't cooperate...
- library(foreign) for datasets from Stata and beyond (check the documentation!)
- defining functions
- syntax for defining functions: show the my.mean function
- calling functions repeatedly (your own or others) with apply(), lapply(), sapply()
- debugging with print()
- demonstrate w my.mean()
- stuff related to distributions
- rep()
- seq()
- sample(); and sampling into data.frames
- dates with POSIXct(). dates will almost always be given to you as characters, and you need to parse them
- tapply(), and putting things back into data.frames
- merge()