QGIS Python Programming Cookbook（Second Edition）

封面

版权信息

Credits

About the Author

About the Reviewer

www.PacktPub.com

Customer Feedback

Preface

Chapter 1. Automating QGIS

Introduction

Installing QGIS 2.18 for development

Using the QGIS Python console for interactive control

Automatically starting the Python console

Using the Python's Script Runner plugin

Setting up your QGIS IDE

Debugging QGIS Python scripts

Navigating the PyQGIS API

Creating a traditional QGIS plugin

Creating a Processing Toolbox plugin

Distributing a plugin

Building a standalone application

Storing and reading global preferences

Storing and reading project preferences

Accessing the script path from within your script

Chapter 2. Querying Vector Data

Introduction

Loading a vector layer from a file sample

Loading a vector layer from a geodatabase

Examining vector layer features

Examining vector layer attributes

Filtering a layer by geometry

Filtering a layer by attributes

Buffering a feature

Measuring the distance between two points

Measuring distance along a line

Calculating the area of a polygon

Creating a spatial index

Calculating the bearing of a line

Loading data from a spreadsheet

Accessing layer metadata

Chapter 3. Editing Vector Data

Introduction

Creating a vector layer in memory

Adding a point feature to a vector layer

Adding a line feature to a vector layer

Adding a polygon feature to a vector layer

Adding a set of attributes to a vector layer

Adding a field to a vector layer

Joining a shapefile attribute table to a CSV file

Changing vector layer geometry

Changing a vector layer feature's attribute

Removing data from a vector layer

Deleting a vector layer feature's attribute

Reprojecting a vector layer

Converting a shapefile to KML or GeoJSON

Merging shapefiles

Splitting a shapefile

Generalizing a vector layer

Dissolving vector features

Performing a union on vector shapes

Rasterizing a vector layer

Exporting a layer to the GeoPackage format

Chapter 4. Using Raster Data

Introduction

Loading a raster layer

Loading a NetCDF file

Getting the cell size of a raster layer

Obtaining the width and height of a raster

Counting raster bands

Swapping raster bands

Querying the value of a raster at a specified point

Reprojecting a raster

Creating an elevation hillshade

Creating vector contours from elevation data

Sampling a raster dataset using a regular grid

Adding elevation data to a line vertices using a digital elevation model

Creating a common extent for rasters

Resampling raster resolution

Counting the unique values in a raster

Mosaicing rasters

Converting a TIFF image to a JPEG image

Creating pyramids for a raster

Converting a pixel location to a map coordinate

Converting a map coordinate to a pixel location

Creating a KML image overlay for a raster

Classifying a raster

Converting a raster to a vector

Georeferencing a raster from control points

Clipping a raster using a shapefile

Chapter 5. Creating Dynamic Maps

Introduction

Accessing the map canvas

Changing the map units

Iterating over layers

Symbolizing a vector layer

Setting a transparent layer fill

Using a filled marker symbol

Rendering a single band raster using a color ramp algorithm

Setting a feature's color using a column in a CSV file

Creating a complex vector layer symbol