Sankey charts are a powerful visualization tool that allow us to understand the flow of data or resources in a system. They are named after their inventor, the Scottish engineer and physicist, Captain Matthew Newson Sankey. These charts use color-coded arrows to show the movement and distribution of data between different points or nodes. In this article, we will explore how to create and use sankey charts to make informed decisions based on the colorful connections they show.
Creating a Sankey Chart:
Creating a sankey chart can be quite straightforward using various software platforms such as R, Python, and Excel. First, you need to gather the data for your chart. This data should be in a table format with three main columns representing the source, target, and the flow between them.
In Python, one may use the networkx library to visualize sankey diagrams. networkx is a python package for the creation, manipulation, and study of the structure, dynamics, and functions of complex networks. Here is an example of how to use networkx to create a sankey chart:
“`python
import networkx as nx
import matplotlib.pyplot as plt
import pandas as pd
Load your data from a csv or excel file
data = pd.readcsv(‘SankeyDATA.csv’)
Prepare the data
source = data[‘Source’].values
target = data[‘Target’].values
value = data[‘Value’].values
Create the nodes
nodes = set(source + target)
Create the sankey diagram
G = nx.DiGraph()
G.addedgesfrom(zip(source,target),weight=value)
Draw the sankey diagram
pos = nx.shelllayout(G)
plt.figure(figsize = (8,8))
nx.drawnetworkxnodes(G, pos, nodesize = 500, nodecolor=’grey’, alpha = 0.5)
nx.drawnetworkxlabels(G, pos)
nx.drawnetworkxedges(G, pos, width=5.,edgecolor = ‘b’, arrows=True)
nx.drawnetworkxedges(G,pos, edgelist=G.edges(),
width=5, alpha=0.5, edge_color=’b’, style=’dashed’)
plt.show()
“`
In this code, we use the pandas library for data handling, and the networkx library to create the sankey chart. The value column in your data represents the amount of flow between each source and target.
Applications of Sankey Chart:
Sankey charts have numerous applications in various fields. They’re commonly used in industry, engineering, and business to show resource allocation, process flows, and data distribution. Some of the most common applications include:
- Energy Flow Visualization: For instance, demonstrating the energy consumption and efficiency of different systems in buildings.
- Financial Flows: In banking and finance, sankey charts can show the movement of funds in different transactions.
- Data Flow in Software: In software engineering, it can illustrate the flow of data between different entities in a system.
- Supply Chain Analysis: It can assist in visualizing the supply chain process from manufacturing to distribution.
- Environmental Processes: Visualizing the flow of resources in ecosystems.
Key Tips for Effective Use:
1. Color Usage: Use distinct colors for different sources or categories to easily distinguish between them. This makes the chart visually appealing while also aiding in understanding complex flows.
2. Labeling: Clearly label both the sources and targets of the flow. Including text descriptions associated with each flow can provide context.
3. Simplification: Avoid overly complex charts with too many paths. For more complicated flows, consider breaking down the data into smaller subsets to keep the chart comprehendible.
4. Focus on Key Flows: Identify and highlight major flows in the data, which might be critical for decision-making. This could be done by increasing the size of the arrows or using a different color for key flows.
In conclusion, sankey charts serve as a valuable tool in data analysis and presentation, enabling users to make more informed decisions based on their visual interpretation of data flows. With the right use of color, clarity, and simplification, these charts can make complex data easily accessible and understandable, guiding users through a wealth of information in a visually engaging manner.
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.
