geoscript raster math.groovy

File file = new File("earth.tif")
GeoTIFF geotiff = new GeoTIFF(file)
Raster raster = geotiff.read("earth")

File arcGridFile = new File("earth.asc")
ArcGrid arcGrid = new ArcGrid(arcGridFile)
arcGrid.write(raster)
Raster arcGridRaster = arcGrid.read("earth")

arcGridRaster.eachCell {double value, double x, double y ->
    double newValue = value + 100
    arcGridRaster.setValue([x,y], newValue)
    assert newValue == arcGridRaster.getValue([x,y])
}

File arcGridFile2 = new File("earth_add.asc")
ArcGrid arcGrid2 = new ArcGrid(arcGridFile2)
arcGrid2.write(arcGridRaster)
Raster arcGridRasterAdd = arcGrid2.read("earth_add")

arcGridRaster.eachCell {double value, double x, double y ->
    println "${x},${y} ${value} = ${arcGridRasterAdd.getValue([x,y])}"
    assert value == arcGridRasterAdd.getValue([x,y])
}