Working With Raster Calculator In ArcMap

Raster Calculator extracts information from a Raster Image, based on user requirements.

Image by James Osborne from Pixabay

Working with Raster Calculator

To explore the highest elevation areas in your DEM raster e.g. select Spatial Analyst Tools à Map Algebra

Raster Calculator Tool

Raster Calculator

Double click on the layer e.g. in my case it is DEM_Layer or any raster of your choice, to enter this into the ‘search’ window. Click on the “>” symbol e.g. and select a number less than the maximum elevation. Query can change based on your criterion. This arithmetic raster operation will select all cells with values above the defined threshold. In the example below a threshold of 500m was used.

A new layer appears on your map. The majority of the map has a 0 value representing false (values below the threshold), and the colored region has a value of 1 representing true (elevations higher than 500 meters). You can play with colors to make it easier to spot the filtered areas.

Similarly you can extract any information from a Raster Imagery in ArcMap.

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