Ggplot2

ggplot2 is a plotting tool for R

Usage

Resources

• Top 50 ggplot2 Visualizations - The Master List
• ggplot2 error bars

Bar Chart

Example bar graph:

data(mtcars)
library(ggplot2)
ggplot(mtcars, aes(x=cyl, y=wt)) + 
  geom_bar(stat="identity", fill="steelblue") +
  xlab("Cylinders") + 
  ylab("Weight (1000 lbs)") + 
  ggtitle("Car Weight vs Cylinders") +
  theme_gray() + 
  theme(plot.title = element_text(hjust = 0.5))

Saving Images

ggsave documentation

# Save as PDF
ggsave("barchart_example.pdf", plot=plt, width=6, height=4, device="pdf")
embedFonts(path.expand("barchart_example.pdf"))

# Save as PNG
ggsave("barchart_example.png", plot=plt, width=6, height=4, dpi=300)

For embedding in a latex file, I recommend exporting as PDF. This allows exporting as a vector format with text.
If you must export as a raster image (jpeg, png), set the dpi flag to get a high-resolution image.

Note that embed fonts requires ghostscript:

apt-get install ghostscript -y

Legends

Customizing FAQ
guide_legend

# Move legend to the bottom
plot <- plot +  theme(legend.position = "bottom")

# Set color legend to have two rows
plot <- plot +  guides(color=guide_legend(nrow=2, byrow=TRUE))