Attribute Linking: Making Eonfusion a powerful analysis tool
One of the most powerful analysis features of Eonfusion is the ability to easily migrate attributes between and within datasets. While there are specific operators in Eonfusion to accomplish this (eg. Copy Raster attribute to Vertices), the real potential comes from the generic ability to create links between and within datasets. Eonfusion uses links to represent the relationships between data sets and within data structures which can be traversed in order to copy attributes directly, or perform customized analysis.
There are a number of ways to generate links in Eonfusion:
- Fusion discovers all instances of coincident or overlapping data in a given geometric space, and creates links between coincident data items. A list of dataflow tutorials that use Fusion can be found in the User Forum.
- Join Attribute Groups: performs a standard table join based on a specified attribute - so items in separate datasets with the same attribute value will be linked.
- The Evaluate Expression operator can be used prior to the Join Attribute Groups operator to create a new attribute (some combination/calculation based on existing attributes in the dataset) to use in the Join operation.
- Aggregate Features: groups features within a dataset with the same attribute value - while retaining links to the original features.
- Create links between neighbouring vertices within a vector dataset that are connected in a line or a surface feature.
- Version 2.0 has two new neighbour linking operators. "Link Neighbouring Vertices" and "Link Neighbouring Raster Cells" both generate links that can subsequently be used to perform an almost limitless range of proximity-based analysis.
And there are also a number of ways you can use links to add value to your data:
- These links may be used to transfer attributes between attribute groups with the Copy Attribute operator
- If a link is a one-to-many link (i.e. it is pointing from a single item in one dataset to multiple items in another) there are some simple Link Statistics you can perform when traversing the link e.g Follow the First or Last Link, Count the Links or find the Min or Max attribute value for all the links.
- Links can be traversed in the Expression Evaluator for customised analysis e.g. to calculate the direction of travel along a line.
A worked example of the density estimation method shown in the Puma Tracking case study in this newsletter, which shows the power of attribute linking in action, can be downloaded from the User Forum
