geom_freqpoly


Plot the distribution of a single continuous variable by dividing the x axis into bins and counting the number of observations in each bin. Frequency polygons display the counts with lines. Frequency polygons are more suitable when you want to compare the distribution across the levels of a categorical variable.

Aesthetics

x required position aesthetic
alpha, colour, group, line type, size classic aesthetics properties

Other Properties

binwidth The width of the bins. Can be specified as a numeric value, or a function that calculates width from x. The default is to use bins that cover the range of the data. You should always override this value, exploring multiple widths to find the best to illustrate the stories in your data. The bin width of a date variable is the number of days in each time; the bin width of a time variable is the number of seconds.

Computed Variables

count number of points in bin
density density estimate
ncount count, scaled to maximum of 1
ndensity density estimate, scaled to maximum of 1

Similar Geometries

geom_histogram, geom_line

Description and Details

Using the described geometry, you can insert a simple geometric object into your data visualization – a frequency line defined by a position aesthetic property x. You can find this geometry in the ribbon toolbar tab Layers, under the 1D button.

Using the geom_freqpoly geometry, you can display the distribution of values from one continuous dataset variable. For example, we use the price variable from the built-in diamonds dataset. The resulted frequency line is shown in the following plot.

For frequency lines you can define an auxiliary parameter that has an important influence on the final shape of the curve. This parameter is named binwidth and defines the width of bins. binwidth can be defined as a numeric value, or as a function that calculates width from x aesthetic property. On the following example, we changed the default value to 100.

In the case, you can divide your dataset by a categorical variable into several groups, you can display frequency lines for each category. The following figure shows an example, where selected dataset was divided according to the diamonds quality categories (cut variable). For this purpose, the cut variable was mapped to color aesthetic property.

For a further dataset categorization, you can use the facet_wrap object, which allows you to display the lines for sub-groups of diamonds that are divided not only by diamonds quality, but also by diamonds color.

In addition to the described geometry, you can also use the geom_histogram geometry layer to Plot the distribution of a continuous variable.