Tutorial9_WritingFunctions.Rmd

% Tutorial 8: Advanced Topics
% DPI R Bootcamp 
% Jared Knowles

```{r setuph, include=FALSE}
# set global chunk options
opts_knit$set(animation.fun=hook_r2swf)
opts_chunk$set(fig.path='figure/slides8-', cache.path='cache/slides8-',fig.width=12,fig.height=9,message=FALSE,error=FALSE,warning=FALSE,echo=TRUE,size='tiny',dev='png',out.width='700px',out.height='500px',cache=TRUE)
library(eeptools)
library(ggplot2)
load('data/smalldata.rda')
```

# Overview
In this lesson we hope to learn:
- How to write a basic function
- How to include error checking within a function
- User specified options within a function
- Writing your own R method
- Writing generic functions for R methods

# Why write a function?
- Aren't current R functions perfectly good?
- Can't I find a package to do this for me?
- If I write the function wrong won't R crash or my analysis be incorrect?
-