---
title: "R Notebook Tutorial"
author: "Sean Horvath"
date: "`r format(Sys.time(), '%d %B, %Y')`"
output:
  html_notebook: default
  pdf_document: default
---

This is an [R Markdown](http://rmarkdown.rstudio.com) Notebook. When you execute code within the notebook, the results appear beneath the code.

# The Basics
### Simple R chunk
Run code in *chunks* like below:
```{r}
my_matrix <- matrix(c('a','b','c',1,2,3),nrow=3)
my_matrix
class(my_matrix[1,1]);class(my_matrix[1,2])


my_df <- data.frame(Char=c('a','b','c'),Num=c(1,2,3))
my_df
class(my_df[1,1]);class(my_df[1,2])


my_df <- data.frame(Char=c('a','b','c'),Num=c(1,2,3),
                    stringsAsFactors=F)
my_df
class(my_df[1,1]);class(my_df[1,2])

my_df[1,2]
my_df$Num[1]
```

### Only display the output
You can use **chunk options** to control how individual R chunks are displayed.
```{r echo=FALSE}
library(reshape2)

names(airquality) <- tolower(names(airquality))
head(airquality)

aqm <- melt(airquality, id=c("month", "day"), na.rm=TRUE,
            variable.name='Atmosphere',value.name='Measurement')
head(aqm)
```

Some useful chunk options are  
`warnings=FALSE`  
`message=FALSE`  

### Font colors
Roses are $\color{red}{\text{red}}$, 
violets are $\color{blue}{\text{blue}}$