NOTE: The CookBook by Yves on GitHub provides many useful code examples for geomatics professionals. This YouTube channel also offers a wealth of resources.

Shapely: Geometric Operations in Python

Shapely is a powerful Python library for manipulating planar geometric objects. It is built on the GEOS library (used by PostGIS) and provides:

  • Support for various geometry types: points, lines, polygons, multipoints, etc.
  • Geometric operations: intersection, union, difference, distance.
  • Geometry attributes: area, length, centroid.
  • Seamless integration with libraries like GeoPandas and PyQGIS.

Example: Creating a point and a polygon:

from shapely.geometry import Point, Polygon

# Create a point
point = Point(0, 0)

# Create a polygon
polygon = Polygon([(0, 0), (0, 1), (1, 1), (1, 0)])

📘 Shapely Documentation
🎥 Shapely Essentials in a Few Minutes

Rtree: Fast Spatial Indexing

Rtree provides spatial indexing and search capabilities using R-tree data structures. It is often used alongside Shapely and GeoPandas for spatial queries.

Key features:

  • Nearest neighbor search
  • Spatial containment and intersection queries
  • Multi-dimensional indexing
  • Disk-based storage and fast loading

Example: Finding the nearest object to a point:

from rtree import index

# Create an Rtree index
idx = index.Index()

# Insert points
idx.insert(1, (0, 0, 0, 0))
idx.insert(2, (1, 1, 1, 1))

# Search for the closest point to (1, 1)
results = list(idx.nearest((1, 1, 1, 1), 1))
print(results)

📘 Rtree Documentation
🎥 Why Use Rtree? (Short Explanation)

Django & GeoDjango: Web Development with Spatial Support

Django is a high-level Python web framework based on the MVC (Model-View-Controller) pattern. GeoDjango extends it to support geographic data and spatial operations.

Core features:

  • URL routing and view handling
  • ORM for database access and manipulation
  • Templating system for dynamic HTML rendering
  • Middleware and form validation
  • Integration with PostGIS for spatial queries via GeoDjango

📘 Django Official Website
🎥 Useful Videos:

QGIS & PyQGIS: Plugin Development for GIS

QGIS is a free and open-source desktop GIS application written in C++. It supports Python through the PyQGIS API, allowing developers to build plugins that interact with spatial data.

To build a QGIS plugin:

  1. Use Qt Designer to create the plugin interface.
  2. Use Plugin Builder to generate the plugin’s structure.
  3. Write Python code using the QGIS API to implement functionality.

💡 Tip: Development is accelerated by tools like Plugin Builder, but familiarity with PyQt5 and the QGIS API is essential.

📘 PyQGIS Developer Cookbook
🎥 Helpful Videos:

Additional Resources