Density

Density

The Density node creates density plots using ggplot2 to help you visualise the distribution of a single variable in your data. Unlike a histogram, a density plot shows a smooth continuous curve estimated from the data.

What it does

  • Creates a density plot from one column of your dataset
  • Optionally fill areas by a grouping variable
  • Supports adjustable bandwidth smoothing
  • Supports custom axis labels
  • The plot can be downloaded as a PNG image

How to use it

  1. Connect a data source — drag an edge from an Input CSV node
  2. Select a variable — choose which column to plot
  3. Optionally configure — set a fill variable, bandwidth adjustment, or custom axis labels
  4. Click Run — the density plot is generated and displayed

Configuration

Setting Required Description
Upstream connection Yes A node providing data
Variable Yes The column to plot on the x axis
Fill variable No A grouping variable to fill areas by
Bandwidth adjust No Smoothing multiplier (default: 1). Values > 1 smooth more, < 1 smooth less
X axis label No Custom label (defaults to column name)
Y axis label No Custom label (defaults to “Density”)
Comment No Annotation for generated R code

Output

The Output tab displays:

  • The density plot as an image
  • A Zoom button to view the plot full-screen
  • A Download plot button to save it as a PNG file (named density_{variable}.png)

Generated R code

Basic density plot:

library(ggplot2)
ggplot(data = my_data, aes(x = height)) +
  geom_density() +
  theme_classic()

With fill variable, adjusted bandwidth and custom labels:

library(ggplot2)
ggplot(data = my_data, aes(x = height, fill = species)) +
  geom_density(adjust = 2, alpha = 0.4) +
  theme_classic() +
  labs(x = "Height (cm)", y = "Frequency")

Tips

  • Choose a numeric column to get a meaningful density plot
  • The fill variable is useful for comparing distributions across groups
  • When using a fill variable, areas are overlaid with transparency so you can see all distributions
  • Increase the bandwidth adjust value (e.g. 2 or 3) if the curve is too noisy, or decrease it (e.g. 0.5) to show more detail
  • You can download the plot for use in reports or presentations