Performing Selection by Location in ArcMap 10.2

Selection by Location is the process of querying the spatial component of the database. This selecrion process usually asks information that have to do with the spatial relationship an object has with other objects around it.

For example, in a GIS, a road normally passes over the land use and a building can be within a cluster of trees. These spatial relationships are defined by the topology.

Today in this powerpoint presentation, we intend to demonstrate the following-

- how to carry out a Spatial query using ArcMap;
- A demonstration of the application of the Selection by Location to helping a Utility Company solves a Tariff dispute.

Feel free to send your comment and feedback


 

Converting KML layers created in google earth images to feature layers in ArcMap using ArcToolBox

CLICK ON THE LINK TO VIEW AND DOWNLOAD PROCEDURE

We saw two advantages from this process and we are still working on other inconsistencies.

1. The slight shift and inconsistencies generated when having to georeference images will be reduced if not totally eliminated.
2. Google satellite imagery can now serve as a ground control for the GPS when ground truthing exercises are carried out.


Task
We will demonstrate how to import vector layers created from google earth in ArcMap using ArcToolBox.

CLICK ON THE LINK TO VIEW AND DOWNLOAD PROCEDURE

Converting KML layers created from Google satellite images to shapefiles using DNR GPS and ExpertGPS

CLICK ON THIS TO VIEW AND DOWNLOAD PROCEDURE

We will carry out this process in many ways but all geared at demonstrating how to trace out features (points, lines and polygons) on your google satellite imagery and convert these vector layers into shape files. We have about four separate approaches using DNR GPS, ExpertGPS, Arcmap and QGIS.

Task

We demonstrate how to features traced from a google satellite image are saved as kml file and converted to shape files using DNR GPS and ExpertGPS.

You can download ExpertGPS one week trial version to practise.

CLICK ON THIS TO VIEW AND DOWNLOAD PROCEDURE

Digitizing point, line and polygon features into shape files QGIS

This is a continuation of our QGIS series. We started with Georeferencing (See previous post ‘Georeferencing a raster image using QGIS’) and today we will demonstrate how to digitize a raster image to create point, line and polygon shape files.


Watch and follow the video lessons carefully and send any questions, comments or observations through our feedback page. I must chip in that it is quite tasking to show the process of digitizing offsite, but we hope it is made as simple as possible. Sorry, we couldn’t add sound as this would make the video too heavy to embed, we are working on that technicality.


Tips

• Mouse Right Click on the Layer when you want to Open the attribute table
• Make sure the layer you are creating and the raster image have the same spatial reference. Note how the spatial reference was changed in the video – ‘Digitizing polygon features’.
• The ID field on the attribute table serves as index key to join database or tables.
• Right click when u finish tracing a feature so the table to fill will pop up.
• To delete the trace, open the attribute table, select it and use the trash bin icon to delete it.

Point features -https://drive.google.com/file/d/0B8z8JZ83pZMaTnlyT0kzTUtSOVE/view?usp=sharing
Line features https://drive.google.com/file/d/0B8z8JZ83pZMabVJLekEwQTRfR1E/view?usp=sharing
Polygon features https://drive.google.com/file/d/0B8z8JZ83pZMaT2p2OW9fQ0RBZ1U/view?usp=sharing


Hope you have started practicing yourself. remember to feel  free to comment.