Flow map

1.1 Application scenarios

The flow map displays information or the movement of objects from one location to another and the number of objects on the map.

Usually used to display migration data of people, animals, and products. The scale or number of movements represented by a single flow line is represented by its thickness, which helps to show the geographical distribution of migration activities.

The flow map is mostly used in scenarios such as interregional trade, traffic flow, population migration, shopping and consumption behavior, communication information flow, and aviation routes. It can also be applied to enterprise cargo transportation and supply chain management.

For example, the movement path of migrants during the Spring Festival travel season is shown in the following figure: 

1.2 Basic requirements

1.3 Chart features

Advantages: It is suitable for showing changes in the corresponding data when things move in geographic space.

Disadvantages: Not suitable for displaying precise values.  

2.1 Data description

Download sample data: Spring Migration Data.xlsx

and upload it to FineBI.

Several necessary fields of the flow map:

Geographical field: For example, "City" in the figure below, you can get longitude and latitude after converting to geographic role.

Migration route: corresponding to each migration route, such as Nanjing City-Sanya City, Nanjing City-Zhongwei City, each route contains two cities.

Number: Used to define the connection sequence, the sequence is from the small value to the large value. For example, the number of Nanjing is 0 and that of Sanya is 1. The connection sequence of the route "Nanjing-Sanya" is from Nanjing to Sanya. 

2.2 Create a flow map

Create the component as shown in the figure below: 

2.2.1 Convert fields into geographic roles

1) Geographic fields are required to make map components, select "City drop-down>Geographic role>City". As shown below: 

 2) Match the "city" field with the geographic information of the system. Click OK, as shown in the figure below: 

2.2.2 Making a flow map

1) Select the chart type as flow map. And drag in the fields in the analysis area and the graph attribute area, as shown in the following figure:

Note: In the fine-grained column, "Migration Route" must be above "City". 

2) Drag the "Migrant Number" into the color bar and change the gradient scheme to "Aurora". In this way, the number of migrants can be mapped to the color of the connection, as shown in the following figure: 

2.3 Beautify the flow map

2.3.1 Set connection style

Click the connection bar, set the connection to "curve", and the mark point to "none", as shown in the figure below: 

2.3.2 Set blinking animation

Note:Due to the problem of system self-adaptation, you can drag the "number" field into the "tag" column below, set the "flashing animation", and then drag it back to the "connection" column

1) Select "Dropdown>Special Display>Flashing Animation" in the "Number" field under the graphics properties, as shown in the figure below: 

2) Click "Add", select the flashing time interval as 5 seconds, and click "OK", as shown in the figure below: 

2.3.3 Hide legend 

Under "Component Style", choose not to check "Legend", as shown in the figure below: 

2.3.4 Modify GIS backgroud

Select "Component Style>Background" and change the GIS background to dark blue, as shown in the following figure:

2.4 Effect view

2.4.1 PC

2.4.2 Mobile

Complete the dashboard, see: Flow Map