Sunday 11 April 2021

How To Creating Geodatabase and Feature Class in ArcGIS

Introduction

                          Now you are going to begin digitizing features of this image. Digitzing is the process of making features we can see on the toposheet (name of image or toposheet) image editable and making them features to which additional spatial and non - spatial attributes can be assigned. This means we are going to follow a process of making digital versions of objects that will have an attribute table associated with them. our primary goal will be digitizing the wards, which are objects that occupy an area on the map, once they are digitized and have an associated attribute table these objects will also be  known as polygons features. in an accompanying document  you have data on the home country of mother by ward. when digitizing we can digitize point, line, and polygon. by digitizing these features you make them available for mapping once you have added the tabular data to the attribute table "as you know there are a few ways can do this" the digitizing process is started by creating new layers in ArcCatalog and then adding features to them in ArcMap.

What is Digitization in GIS ?

Digitization in GIS is the process of converting geographic data a scanned image into vector data by tracing the features. Digiting process, features from the image are captured as coordinates in point, line, and polygon formatting.

Summary

ArcGIS can digitize or trace features without mouse or puck click using several.
options: streaming, tracing or freehand drawing. with these methods, the mouse pointer is trace the desired feature.

Procedure

There are three options provided to do this:-
Digitize by streaming, Digitize by tracing, and Digitize by freehand drawing.

Digitize by tracing

Tracing is used to create a new feature which follow the shape of an existing feature. Tracing can be done by tracing directly over an existing feature or at an offset value.

1. Start an edit session.

2. Navigate to editor toolbar, and click the Create Features button. This opens the Create Features window.

3. Select the layer to edit and the Construction tools.

4. Navigate to the editor toolbar, and click the trace tool.

5. Click the map, and start tracing by moving the pointer.


6. To close the tracing session, right-click > Finish Sketch.

7. To complete one part of digitizing a feature, right-click > Finish Part. click the map again to start digitizing another feature.

Digitize by freehand drawing

Freehand drawing is used to create lines according to the movement of the pointer. The segments created are smooth and features or boundaries on the map. This option is suitable for drawing quick, free-forming lines on the map.

1. Start an edit session.

2. Navigate to the editor toolbar, and click the Create Features button. This open the Create Features window.

3. Select the layer to edit.

4. For Construction tools, select Freehand.


5. Click the map, and start the freehand drawing by moving the pointer.

6. Click the map once to stop the drawing session.

Creating Geodatabase and Feature Class

Step-1 Click Add Data and add the given toposheet (TIF File).





Step-2 Open Arc Catalog.


Step-3 Click on the destination folder where to create the Geodatabase.


Step-4 Right click on the folder.



Step-5 Click ‘New’ and another dialogue box appears.


Step-6 Click on either ‘File Geodatabase’ or ‘Personal Geodatabase’ to create a new Geodatabase.


Step-7 A new Geodatabase will be created and rename the Geodatabase according to our wish.

Here, ‘toposheet geo.tif’ is the given name for the created Geodatabase where.gdb is the extension of the Geodatabase.

Right click on the created ‘toposheet.geo’ and new dialogue box will appear.

Step-8 Click on the ‘Feature class’ to create new feature classes.

A new dialogue box will appear in which name of the new feature class and the type of    feature such as point, line polygon is given and new feature classes are created.

Step-9 Here, point feature is created.

After entering the name and type click next.

Step-10 On clicking next, co-ordinates are selected for the feature class.


Here, WGS1984  UTM  Zone 43N is selected according to the selected Toposheet. Note-(study area Change the coordinating system to suit you will be selected))


Step-11 Click next.

Step-12 Click next.


New feature class is created.


Likewise the point and polygon feature classes are created.


The selected grid shown in the image is used for further digitization by creating point, line and polygon shape files.

Step-13 Digitize the point features (home).


Step-14 Digitize the line features (road).


Step-15 Digitize the polygon features (field).




 *Finalize the map.


                                          ArcMap Digitization Practice Video...






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