ASCII GRID INFORMATION



The ASCII grid file consists of header information containing a set of keywords, followed by cell values in row-major order. The file format is:

<ncols xxx> (4837 for DEM)
<nrows xxx> (5637 for DEM)
<xllcorner xxx> (in UTM coordinates, 306550.00000000 for DEM)
<yll corner xxx> (in UTM coordinates, 5419550.00000000 for DEM)
<cellsize xxx> (cell size = 100 for the DEM)
{nodata_value xxx} (value = -9999 for the DEM)
row 1
row 2
.
.
.
row n


- Where xxx is a number, and the keyword nodata_value defaults to -9999.  Row 1 of the data is at the top of the grid, row 2 is just under row 1 and so on.

- The nodata_value is the value in the ASCII file assigned to those cells whose true value is unknown.

- Cell values should be delimited by spaces.  No carriage returns are necessary at the end of each row in the grid.  The number of columns in the header is used to determine when a new row begins.

- The number of cell values must be equal to the number of rows times the number of columns.
