#### Overview of this book

R Graph Essentials
Credits
www.PacktPub.com
Preface
Free Chapter
Base Graphics in R – One Step at a Time
Creating Graphs with ggplot
Index

## Creating bar charts

Now, let's use `qplot` to produce a frequency bar chart; in this case, for the categorical variable `TREATMENT`. The heights of the bars give the counts of patients receiving each treatment. We choose a nice hue of brown from the Hexadecimal Color Chart. To create a bar chart, we use `geom = "bar"`. Enter the following syntax:

```qplot(TREATMENT, data = T, geom = "bar",  binwidth = 5, xlab = "HEIGHT (cm)", ylab = "FREQUENCY", fill = I("#CC6600"), color = I("blue"))
```

Here is our bar chart:

The following is a more complex example involving bar charts. We set up a new dataset relating to dinners purchased by two people at fast food outlets during one week. Enter the following syntax into R:

```dinners = data.frame(person=c("Thomas", "Thomas", "Thomas", "James", "James"), meal = c("curry", "stew", "salad", "fish", "stir-fry"), price = c(15, 18, 12, 25, 13))

dinners
```

The output is as follows:

```  person     meal  price
1 Thomas    curry    15
2 Thomas     stew    18