Introduction
This article looks at Astrato's Sankey visualization.
A Sankey Chart (alluvial diagram) data object consists of two or more dimensions and one measure.
The Saneky chart gives users a view of data flow between the different dimensions.
Sankey chart insights identify the significance of a path that connects all the dimensions in the chart.
Sankey chart common use cases are:
Energy Flow Diagrams
Material Flow Analysis
Cost Allocation Diagrams
Supply Chain and Logistics
Website Traffic Flow
Population Migration
Carbon Footprint Analysis
Building a Sankey
Add a Sankey Chart
The Sankey Chart can be found in the visualization tile. It is positioned in the bottom part of the visualization list.
Define a SankeyChart
Add at least two dimensions and one measure.
Special Dimension Settings in the Sankey Chart
Coloring: set the coloring method for an individual dimension.
Single - all nodes in the dimension will have the same color
Categorical - each node in the dimension will have a different color.
Data Limits
By default, the chart displays the first 2000 rows of the query.
When using more than 3 dimensions, it's recommended to increase the limit of records to a number that covers all the rows.Large number of rows in a charts might impact the performance of the chart and dashboard.
Style a Sankey Chart
Layout
Show null nodes: show or hide all null nodes across all dimensions.
Compare the two images below and notice the difference in the second dimension when this setting is enabled versus disabled.
Node margin: set the vertical margin between nodes in the dimensions.
Node Labels
Show header label: show or hide the dimensions labels.
Width: set the width of nodes across all dimensions; when nodes are wide enough, labels will be placed on the side of the nodes.
Margin: set the horizontal margin between the links and the nodes.
Node labels: enable or disable node labels.
When enabled, select which information to display:Dimension: only shows the dimension label
Flow: only shows the measure value.
Both: Showing dimension label and measure value.
Placement Priority: by default, the node label is placed automatically in the best position to create a clear display of the chart; by disabling one of the options, you can force a particular place for the node label.
Backdrop: set the background color for the node label.
The image below shows a chart where node labels are set to:
both, and placement priority is set beside, and the backdrop is light green.
Color
Color - set the coloring method for the chart. There are two options:
Single: All nodes and links will be colored the same way.
It's recommended to use this method when wanting to highlight a particular part of the chart.Per Dimension: A different color for each dimension.
* This setting is overriding the color setting of the dimensions
Conditional coloring: define a coloring condition by either a measure or a dimension.
This setting overrides any coloring definition.
Node color- when override is enabled, all nodes will be displayed with the defined color.
Link color: set the color and gradient mode for links
Opacity: set the opacity of links.
Override: set the link color, overriding other settings.
Coloring method:
The left shows a gradient between the start and end dimension colors.
The middle option uses the start dimension color
The right option uses the end-dimension color