QGIS Training

1. This software is the popular QGIS open source GIS software. In this you will learn
how to load data into QGIS from popular GIS formats including shapefiles, geodatavases.
And how to classify features and capturing roads and buildings etc..,
Course Introduction

2. An Overview of the Interface
We will explore the QGIS user interface so that you are familiar with the menus,
toolbars,map canvas and layers list that form the basic structure of the interface.
The elements identified in the figure above are:
•Layers List / Browser Panel
•Toolbars
•Map canvas
•Status bar
•Side Toolbar

3. Exercise data
This module is basically where we do the ‘nitty-gritty’ part of the GIS training to
come-up with final outputs. You will learn how to obtain, create, manipulate, edit
geospatial data by series of tools and commands. The exercises will be done step by step,
along with actual demonstration. The exercises will make you “connect” the theoretical part
of GIS to its actual applications. Data source may take from web maps.

4. Creating a Basic Map
Vector
Vector data is not made up of a grid of pixels. Instead, vector graphics are
comprised of vertices and paths.The three basic symbol types for vector data are points,
lines and polygons (areas). These cartographers use these symbols to represent real world
features in maps.
Points
When features are too small to be represented as point is used. For example
trees, transmission towers and overhead tanks are represented by point feature.

5. Polylines
Vector lines connect each vertex with paths. Basically we are connecting the dots in a
set order and it becomes a vector line with each dot representing a vertex. Lines usually
represent features that are linear in nature. For example maps shows roads, culverts, bridges,
canals and rivers (depends on width) and flyovers.
Here lines are represented by red colour.

6. Polygons
When we join a set of vertices in a particular order and close it, this is now a vetor
polygon feature. Cartographers use polygons to show boundaries and they all have an area. For
example, a building footpriny has a square footage and agricultural fields and village abadis
haing areas.
Captured buildings by using rectangular polygons.

7. Vertex
click on a vertex or segment to enable vertex editing for that feature. Click on vertex
you want to add and move node points.

8. Scale
The scale is a simple ratio of map to ground measurement with a colon between the
two measurements. For example, a scale of 1:1000 means that every one unit on the map is
equal to 1000 units on the ground.
Maximum we digitize date within the range of 1000.

9. Symbology
It is the application of graphic symbols, varied by subclasses, width and other
properties.

10. Adding layers
Open manage layers toolbar (it exist in left side of the screen). Or open data source
manage toolbar. In that we have a new shape file layer.

11. Then create a layer which geometry needed and give file name and create path in your folders.

12. Creating Vector Data
Feature topology
Topology is a useful aspect of vector data layers, because it minimizes errors such as
overlap or gaps.
For example: if two features share a border, and we edit the border using topology,
then you won’t need to edit first one feature, then another, and carefully line up the borders so
that they match. Instead, we can edit their shared bored and both feature will change at the
same time.
Here when we see on the image these are the line rules.

13. Here these are the polygon rules. By using these rules we can run topology

14. Digitization
Digitization is a process of converting raster data to vector data. For this process QGIS
provides many tools for efficient digitization. Digitization should be clean and a copy of the
raster data so that the information of the map does not change.
For example digitization of roads and building

15. Errors detection
When we run the topology rules the errors should find in topology check panel if
errors should be there. Errors can be finding by red marks on vector data.

16. Attribute data
It is used to describe the feature that you want to map. It can include text or numbers
data type. Must be careful in how the different data types are integrated and used.

17. Label tool
Map is not just a picture in GIS, they represent several hidden information of objects.
So in the upcoming days we try to understand it more and unearth the hidden data. After
creating basic map, we try our hands on layer labeling in QGIS use and change label. For
extracting more information about the object we do labeling.

18. Classification
Image classification is one of the most important tasks in image processing and
analysis. It is used to analyze land use and land cover classes. With the help of remote sensing
we get satellite images such as landsat satellite images.

19. Any Queries