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QGIS blueprints : develop analytical location-based web applications with QGIS /
| Clasificación: | Libro Electrónico |
|---|---|
| Autor principal: | |
| Formato: | Electrónico eBook |
| Idioma: | Inglés |
| Publicado: |
Birmingham :
Packt,
[2015]
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| Colección: | Community experience distilled.
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| Temas: | |
| Acceso en línea: | Texto completo |
Tabla de Contenidos:
- Cover; Copyright; Credits; About the Author; About the Reviewers; www.PacktPub.com; Table of Contents; Preface; Chapter 1: Exploring Places
- from Concept to Interface; The software; The development community and dependencies; Data format read/write; Geospatial coordinate transformation; Analysis; Web publishing; Installation; Linux; Mac; Windows; OSGeo-Live; Acquiring data for geospatial applications; Producing geospatial data with georeferencing; Table join; Geocode; Orthorectify; The spatial reference manipulation
- making the coordinates line up; Setting CRS; Transformation and projection
- Visualizing GIS dataThe layer style; Labels; The basemap; Using OpenStreetMap for the basemap data; Avoiding obscurity and confusion; The layer scale dependency; The label conflict; Tile caches; Generating and testing a simple directory-based tile cache structure; Create a layer description file for the TileLayer plugin; Summary; Chapter 2: Identifying the Best Places; Vector data
- Extract, Transform, and Load; Loading data and establishing the CRS conformity; The extracting (filtering) features; Converting to raster; Doing more at once-working in batch; Raster analysis; Map algebra
- Additive modelingProximity; Slope; Combining the criteria with Map Calculator; Zonal statistics; Publishing the results as a web application; qgis2leaf; Summary; Chapter 3: Discovering Physical Relationships; Hydrological modeling; Preparing the data; Filling the grid sinks; Clipping the grid to study the area by mask layer; Modeling the hydrological network based on elevation; Workflow automation with the graphical models; Spatial join for a performant operational layer interaction; The CartoDB platform; Publishing the data to CartoDB; Preparing a CartoDB SQL Query; Generating the test data
- The CartoDB SQL view tabThe QGIS CartoDB plugin; The CartoDB SQL API; Leaflet and an external API: CartoDB SQL; Summary; Chapter 4: Finding the Best Way to Get There; Postgres with PostGIS and pgRouting; Installing Postgres/PostGIS/pgRouting; Creating a new Postgres database; Registering the PostGIS and pgRouting extensions; OpenStreetMap data for topology; Downloading the OSM data; Adding the data to the map; Projecting the OSM data; Splitting all the lines at intersections; Database importing and topological relationships; Connecting to the database; Importing into PostGIS with DB Manager
- Creating the topological network dataAn alternate workflow: topology with osm2po; Using the pgRouting Layer plugin to test; Creating the travel time isochron polygons; Generating the travel time for each road segment; Creating isochron polygons; Converting the travel time lines to points; Selecting the travel time ranges in points and creating convex hulls; Generating the shortest paths for all students; Finding the associated segment for a student location; Calculating the accumulated shortest paths by segment; Flow symbology; Web applications
- creating safe corridors