/// <summary>
/// Makes a snow raster in bgd format from the downloaded SNODAS data file
/// </summary>
/// <param name="snodasDatFile">the SNODAS unzipped data file in .dat format</param>
/// <param name="bgdFile">the output bgd data file</param>
/// <returns>The IRaster object</returns>
public IRaster MakeSnowRaster(string snodasDatFile, string bgdFile)
{
//for masked case rows and columns:
int numCols = 6935;
int numRows = 3351;
//for masked case lat and long bounding box:
Extent maskedExtent = new Extent(-124.7337, 24.9504, -66.9421, 52.8754);
int numCells = numCols * numRows;
//read the SNODAS .dat binary file into an array
Int16[] binaryData = BinaryFileHelper.ReadBinaryArray(snodasDatFile, numCells);
IRaster ras = Raster.Create(bgdFile, "bgd", numCols, numRows, 1, typeof(Int16), new string[0]);
//set the properties of our raster: bounds, projection, NoDataValue
ras.Bounds = new RasterBounds(numRows, numCols, maskedExtent);
ras.ProjectionString = "+proj=longlat +datum=WGS84 +no_defs";
ras.NoDataValue = -9999;
//set the raster's values
for (int row = 0; row < numRows; row++)
{
for (int col = 0; col < numCols; col++)
{
ras.Value[row, col] = binaryData[row * numCols + col];
}
}
ras.Save();
return(ras);
}
public static Int16[] ReadBinaryArray(string fileName, int numCells)
{
int numBytes = numCells * 2;
//reading the file. The data is Big-Endian
using (Stream stream = new FileStream(fileName, FileMode.Open))
{
byte[] rawData = BinaryFileHelper.ReadFully(stream, numBytes);
//we need to swap the byte order in the raw data
Swap(rawData);
Int16[] myArray = new Int16[numCells];
Buffer.BlockCopy(rawData, 0, myArray, 0, numBytes);
return(myArray);
}
}
