I have run a hydrodynamic model which has given me a grid of surface elevations throughout a bay.
I am trying to process the results in ArcMap (or QGIS if needed). My goal is to take the current grid and buffer/expand (not sure of the correct terminology) the extent of the grid by 2 cells the whole way around, and have the new buffered cells inherit the value (water surface elevation value) from the neighboring cells from which they were expanded.
From what I have worked out so far there is an Expand tool in the Spatial Analyst toolbox, however, it only works on integer rasters, and I am dealing with a float raster.
I converted my grid to an esri raster grid (displayed in red below) and then used the expand tool to expand the raster by 2 cells (expanded area displayed in green below). I then used the raster calculator and a Con statement to recopy the float values back to the expanded raster. However, this does not copy any values over to the expanded cells.
So my question is, is there any way to somehow interpolate or use a nearest neighbor type tool to set the values of the expanded cells to the nearby cells from which they were expanded?
I have out together an example image to help me explain my problem:
Any ideas/help would be great!