SIMoN/graphs

SIMoN Granularity Graph Tool

Build granularity graphs used for data translation in the SIMoN software application.

Copyright 2020 The Johns Hopkins University Applied Physics Laboratory Licensed under the MIT License

Description

This tool uses shapefiles to generate two JSON graphs: an abstract graph and an instance graph.

To use the generated graphs, rename the abstract graph to abstract-graph.geojson, and the instance graph to instance-graph.geojson.

Then place these two files in the graphs/ directory so that SIMoN will use them.

Both JSON graphs have 3 key attributes:

• nodes maps to a list of the graph's vertices
• links maps to a list of the graph's edges
• graph maps to a dictionary of the graph's metadata
  • id is a UUID for the abstract-instance graph pair, that both the abstract graph and the corresponding instance graph share
  • projection is the coordinate reference system that the shapefile geometries are defined on
  • granularities are the granularities that the graphs connect
  • min_intersect_area is the minimum area of a wedge node in the instance graph (a node made by intersecting disparate geographic granularities)
  • nodes is the number of vertices in the graph
  • links is the number of edges in the graph
  • counts is the number of vertices in the graph, categorized by granularity
  • areas is the total area of each granularity's scope, that is, the sum of all the node areas of each granularity. Ideally, these areas should be equal so that the graph will have a consistent scope.

Installation

Use Python 3.6 to run the graph construction tools.

1. install libspatialindex

   a. install make, cmake, and a compiler (g++ or gcc)

   b. wget https://github.com/libspatialindex/libspatialindex/releases/download/1.9.3/spatialindex-src-1.9.3.tar.gz

   c. tar xfvz spatialindex-src-1.9.3.tar.gz

   d. cd spatialindex-src-1.9.3

   e. cmake -DCMAKE_INSTALL_PREFIX=/home/username .

   f. make

   g. make install

2. install Python packages

   a. pip install -r requirements.txt

3. test installation

   a. export LD_LIBRARY_PATH=/home/username/lib

   b. python test_installation.py