Sankey charts, a powerful data visualization tool, have emerged as a valuable way to explore data flow and transform information into actionable insights. These charts, known for their unique, layered, and interconnected design, offer a visual representation of the movement and transformation of data in a process or system. By incorporating color coding and node labeling, Sankey charts facilitate a deep understanding of the dependencies, bottlenecks, and efficiency in various domains. Let’s delve into the world of Sankey charts, their creation, and applications.
Introduction to Sankey Charts
A Sankey chart, also known as a flow diagram or flow network, was first introduced by the British scientist, William Sankey, in 1898. It is a network diagram that uses arrows and their lengths to represent data flows and transformations. In essence, each arrow represents a flow quantity, and the thickness of the lines depicts the magnitude of the flow. The starting and ending points of arrows are connected by nodes, representing steps or processes in the flow.
Creating a Sankey Chart with Libraries and Tools
To create a Sankey chart, modern data visualization tools, such as Tableau, D3.js, or Python libraries like Plotly, Matplotlib, and NetworkX, can be employed. Here’s a step-by-step guide using Plotly Python library:
- Data Preparation: Organize your data in a tabular format, with columns representing source (‘from’), destination (‘to’), and the quantity or value of the flow.
- Import Libraries: Import the necessary library, for example,
plotly.graph_objects
ornetworkx
. - * Chart Construction*: Define a
sankey
function, setting the source, target, and values for each flow. - Node Handling: Create nodes for process steps or categories using the ‘nodes’ parameter, including labels and colors.
- Plotting the Sankey: Call the
sankey
function with the nodes and links to visualize the data.
“`python
import plotly.graph_objects as go
data = [
{‘source’: ‘A’, ‘target’: ‘B’, ‘value’: 10},
{‘source’: ‘B’, ‘target’: ‘C’, ‘value’: 8},
{‘source’: ‘C’, ‘target’: ‘D’, ‘value’: 5},
# Add more flows
]
nodes = [
{‘id’: ‘A’, ‘label’: ‘Step 1’, ‘color’: ‘blue’},
{‘id’: ‘B’, ‘label’: ‘Step 2’, ‘color’: ‘orange’},
{‘id’: ‘C’, ‘label’: ‘Step 3’, ‘color’: ‘green’},
# More nodes
]
sankey = go.Sankey(
node = nodes,
link = data,
arrangement=’radial’
)
fig = go.Figure(sankey)
fig.show()
“`
Applications of Sankey Charts
- Process Analysis: Industries like manufacturing, supply chain, and energy can benefit from Sankey charts to visualize the flow of materials, energy, or information between various stages in a process.
- Logistics: In supply chain management, they can be used to track the movement of goods from origin to destination, highlighting bottlenecks or delays.
- Energy Systems: Understanding the energy grid’s flows and conversions across different power sources can be accomplished using Sankey charts.
- Data Integration: Data from multiple sources can be combined to show data transformations during data cleansing or integration, helping to identify missing links and inefficiencies.
- Finance: Bank statements, budget allocation, or cash flow can be represented using Sankey charts to exhibit the flow of funds between accounts and transactions.
Conclusion
Sankey charts, with their striking visual representation of data flow, provide a powerful way to analyze complex systems and help transform information into actionable insights. They can simplify complex processes, uncover hidden patterns, and support decision-making by easily showcasing the dynamics of data movement. Whether for business or science, Sankey charts have become a valuable tool in data visualizations that can enhance our understanding of the world around us.
SankeyMaster
SankeyMaster is your go-to tool for creating complex Sankey charts . Easily enter data and create Sankey charts that accurately reveal intricate data relationships.