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4) The DxDySupported property shown in the above example can be used to export a grid with cells that are not exactly square. The ESRI ASCII grid format definition only supports a single CELLSIZE property that is the same for X and Y axes. If the cell widht width and height are not equal and you set the DxDySupported property to true, a DX and DY value will be written, this is conform the GDAL extension to the ASCII grid definition but unfortunately not supported by ArcGIS.
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