Wednesday, February 21, 2018

QGIS STEPS #1-INSTALLING QGIS || GEOREFERENCING || CREATING FEATURES

HOW TO INSTALL GIS PROGRAM
 Firstly run GIS setup to install it
1.SRS.db (this file is in style folder) : paste this file in C:\Program Files\QGIS 2.18\apps\qgis\resources
2.ESRI_EXTRA.wkt (this file is in software folder) : paste this file in C:\Program Files\QGIS2.18\share\gdal
3.Install(Run the bat file in taudem folder to install 4 program)
4.processing>option>providers>tauDEM>activate check on
5.processing>option>providers>tauDEM>MPI/OPENMPI bin directory>C:\Program Files\Microsoft HPC Pack 2012\Bin
6.processing>option>providers>tauDEM>taudem command line tools directory>C:\Program Files\TauDEM\TauDEM5Exe
7.Setting>option>CRS>click on tab next to textbox>coordinate reference>type nepal in filter>choose Nepal MUTM 84
How to do georeferencing
Plugins>manage and install plugins…>search for “georeferencer gdal” and check on.
Go to raster menu>georeferencer>georeferencer…
Then load the image and add co-ordinates at four corner of the image and save the file.
Error (mean error  is seen at the status bar at bottom)
Go to setting of georeferencer and set
Transformation type = liner
Resampling method = nearest neighbor
Target SRS =EPSG : 40084 Nepal MUTM 84
Output raster = path of file to be saved

Create feature
Point (like village, spot, etc.)
(point layer can also be created from excel file with data of X,Y,Z)
A. creating and saving .shp file
Click on add raster>load the image which is to be kept on background i.e. with reference to this image layers are to be created>go to menu layer>create layer>new shape file layer…> select “point” in Type; leave “File recording” as it is; in new field set: Name = “any name”;Type= “type of data among the four type which are text, whole number, decimal and data”; length = 20,30…,etc.; >click on add to field>click on ok>save the file window apper; save the file.
B. Digitization
Click on the toolbar “toggle edit”(symbol is of single pencil)
Click on add feature
Click on the map to be edited
Set : Id = 100,200,etc. (set same Id for same features like if there are 4 villages then all of them have the same Id )
Set name = “name of the feature”
To edit : right click on the current layer>>click on open attribute table> click on the edit toolbar of the opened window of attribute table
To move : click on the toolbar “move data”>drag the point on map to required loacation
To delete : click “select feature” on toolbar (it has a symbol of mouse)>>click on the feature to be selected>click on the “delete” toolbar


Snap on


Setting>snapping option>all visible layer>select vertex and segment and 10 pixel>click apply
Create feature
Line (like road, river, contour line, etc.)

A. Creating and saving .shp file è same as point. Only difference is to select “line” instead of “point” in type.
B. Digitization
Click on the toolbar “toggle edit”(symbol is of single pencil)
Click on add feature
Click on the map to be edited
Set : Id = 100,200,etc. (set same Id for same features like if there are 4 villages then all of them have the same Id )
Set name = “name of the feature”
Add feature>click on roads for certain length>right click to end
To edit attribute: right click on the current layer>>click on open attribute table> click on the edit toolbar of the opened window of attribute table
To edit the node :
select Node tool (present in the same toolbar as that of add layer, toggle edit, etc.)
double click adds a new node
click on the node and drag to move the node to required location.
To join two features
Go to attribute table by clicking on the toolbar
Select all the features to join
Right click near toolbar and select “Advance digitizing toolbar” (if it is not already present)
This toolbar consists of merge, split, etc.
Click on merge to merge
To split feature
Suppose  a line runs south to north then select split feature toolbar and left click on the east or west part and then left click on the west or east part so that a line is drawn and the line splits.

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