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My Raster

I got 2 different raster layers one of them black and white representing the river road. This river raster has pixel values stand for height. I want to extend the size of river in order to show, if the water increases which areas would be under the water But i don't know how to extent, Also the areas outside of the river raster(transparent in the picture) has no data values. Pixel values in extended areas should have pixel values same as nearest river pixel value. I guess i have to do it with raster calculator. But i can not find out how to code this.

marked as duplicate by Aaron arcgis-desktop Dec 27 '17 at 21:01

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Try using CON in your raster calculator expression. You can use it to specify something like where "river_road" is NULL (or some other value), replace it with the values from the terrain model Conditional evaluation with Con


Check out the Euclidean tool set. If you have float type raster, multiply by 10000 and run euclidean allocation then divide by 10000. In the environment setting of euclidean allocation, set raster mask to size of desired extent.

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