RS_SetValue

RS_SetValue(raster: Raster, bandIndex: Integer = 1, colX: Integer, rowY: Integer, newValue: Double)

SELECT RS_BandAsArray(
               RS_SetValue(
                       RS_AddBandFromArray(
                               RS_MakeEmptyRaster(1, 5, 5, 0, 0, 1, -1, 0, 0, 0),
                           [1,1,1,0,0,0,1,2,3,3,5,6,7,0,0,3,0,0,3,0,0,0,0,0,0], 1, 0d
                           ),
                       1, 2, 2, 255
                   )
           )

[1.0, 1.0, 1.0, 0.0, 0.0, 0.0, 255.0, 2.0, 3.0, 3.0, 5.0, 6.0, 7.0, 0.0, 0.0, 3.0, 0.0, 0.0, 3.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]