Qgis manual 2.0




















Module: Creating a Basic Map 1. Lesson: Working with Vector Data 2. Lesson: Symbology 4. Module: Classifying Vector Data 5. Module: Creating Maps 6. Module: Creating Vector Data 7.

Module: Vector Analysis 8. Module: Rasters 9. Module: Completing the Analysis Module: Plugins Module: Online Resources Module: Assessment Appendix: Contributing To This Manual Answer Sheet Indices and tables. To see all the data available to you, with the roads layer selected in the Layers panel: Click on this button: It will show you a table with more data about the roads layer.

You may now close the attribute table. It will give you a new dialog. In this dialog: Click the New button. In the same folder as the other data, you should find the file landuse. Outdated version of the documentation.

Find the latest one here. In this case you can enter the coordinates manually. In this case you can enter the coordinates by clicking on the reference dataset loaded in QGIS map canvas.

Figure Georeferencer 1: Georeferencer Plugin Dialog. The raster will show up in the main working area of the dialog. Once the raster is loaded, we can start to enter reference points. For this procedure you have three options: Click on a point in the raster image and enter the X and Y coordinates manually. Click on a point in the raster image and choose the button from map canvas to add the X and Y coordinates with the help of a georeferenced map already loaded in the QGIS map canvas.

With the button, you can move the GCPs in both windows, if they are at the wrong place. Continue entering points. You should have at least 4 points, and the more coordinates you can provide, the better the result will be.

There are additional tools on the plugin dialog to zoom and pan the working area in order to locate a relevant set of GCP points. Figure Georeferencer 2: Add points to the raster image. Figure Georeferencer 3: Defining the georeferencer transformation settings. Currently, following Transformation types are available: The Linear algorithm is used to create a world-file, and is different from the other algorithms, as it does not actually transform the raster.

The Helmert transformation performs simple scaling and rotation transformations. See Section Custom Coordinate Reference System for information on managing your custom coordinate reference systems. In order to use OTF projection, your data must contain information about its coordinate reference system or you have to define a global, layer or project-wide CRS.

This projection file has the same base name as the shapefile and a prj extension. For example, a shapefile named alaska. QGIS starts each new project using the global default projection. This default can be changed using the [Select This choice will be saved for use in subsequent QGIS sessions. If you want to define the coordinate reference system for a certain layer without CRS information, you can also do that in the General menu of the raster see General Menu and vector see General Menu properties dialog.

However, OTF is not activated by default.



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