Netflower is a tool for visual exploration of flows in dynamic networks, such as money flows between organizations or migration flows between countries. It is a highly interactive web application particularly developed for investigative data journalism.
The tool was developed in the reserach project VALiD.
This tool requires a specific format for the tables in order to visualize them appropriately. Also only .CSV files are accepted. If the required format isn't met, it will result in errors or no displayed data. The format of the table headings defines all further views but needs to be in a specific order.
(1) Prepare your data file as a .csv file with the structure shown in the table.
(2) Load your data here and click 'Load & Show'.
(3) Here you can download some sample files.
(1) The main visualization is a sankey diagram. You read the sankey diagram from left to right. In this example you see the number of Asylum seekers which make an application. The left side show the origin countries and on the right are the destination countries.
(2) The small bar charts left and right show the amount of asylum applications over time from the original country and destination country point of view.
On the bottom of the site, you find two buttons 'Show Less' and 'Show More'. Here you can load more nodes or show less nodes. When you hover over the nodes (rectangles) in the visualization you get the information of how many asylum applications were made from the selected country (node). You also see that maybe not all destination and origin countries are visible by the hatching rectangle. Here you can use the buttons below to load more origin and destination countries.
Detailed view: By clicking on one connection line in the sankey diagram, you get a detail view showing the amount of asylum applications between the two nodes (origin countries and destination countries).
The screen picture shows the visual encoding. There is this example table of asylum data. The lines from the table to the sankey diagram show the encoding from the data to the visual element - in this case a sankey diagram.
You can filter, sort and order the data, which influences the visualization view.
1) You can filter the data in time and connection.
2) You can sort the data by source, target and flow and order it, ascending and descending.
3) Exporting the data from the current view. You get a .csv file with the data of the current visualization, including all sorting and filtering operations.
4) You can limit the number of asylum applications by using the slider on both sides.
5) Search for a particular country in the origin and also in the destination countries using the seach box.
You can use tags to organize and group nodes on the source or target side. You can add tags in the .csv file you will upload, or you can add tags directly in the visualization view.
1) Add tags in the .csv in the 'SourceTag' or 'TargetTag' row. By using the pipe sign '|' you can add more than one tag to a particular node.
2) You can add tags by clicking the tags-sign next to the nodes in the sankey diagram.
3) You can filter by tags by clicking the small button below the search either on the left and right side.
4) To see the flows between given tags you can switch the view in the header, as it is desribed in the video.
5) When you export the data, the tags, you have assigned in the visualization view, are also exported.
You can use a notebook, which opens when clicking the handler on the left side of the screen. You can add some notes and also export it as a .txt. file. This file can be loaded in the notebook sidebar, when starting for example a new session analysing data with netflower.