# Generating a Line Histogram

## Overview

Teaching: 10 min
Exercises: 10 min
Questions
• What kind of scientific question does a line histogram address?

• How do I generate a line histogram with `ggplot2`?

Objectives
• To generate a line histogram using `ggplot2`

Walk through decision making steps from question to chart.

• “How was the population of Africa distributed across the continent by country in 2007?”
• Single variable distribution with many points
• Line Histogram

Implement line histogram.

• `geom_histogram()`
• `geom_density()`

## Line Histogram Fill-in Challenge

Fill in the missing pieces of the following code to generate a line histogram.

``````ggplot(Africa, aes(________, ..count..)) +
geom_density() ________
labs(x = "Log10(________)", y = "Count")
``````

## Output Solution ## Code Solution

``````ggplot(Africa, aes(log10(pop_2007), ..count..)) +
geom_density() +
labs(x = "Log10( 2007 Population )", y = "Count")
``````

## Key Points

• Line histograms represent a single variable distributions with many points.