WMS:GRASS Grid (GSSHA Maps)

WMS can import Geographic Resources Analysis Support System (GRASS) ASCII grid files for use as a background DEM for a GSSHA project. Since it is a simple file format, other digital elevation data can be formatted in the same way and then imported into WMS using the Open command in the File menu.

The card types used in the GRASS ASCII grid file format are self explanatory. The GSSHA model also uses the GRASS ASCII grid file format for all of the map parameters.

GRASS ASCII Grid File Format

Following is an explanation of the content of a GRASS ASCII grid file:

north: n /* Northern boundary grid coordinate */

south: s /* Southern boundary grid coordinate */

east: e /* Eastern boundary grid coordinate */

west: w /* Western boundary grid coordinate */

rows: nrows /* Number of rows in the grid */

cols: ncols /* Number of columns in the grid */

z11 z12 z13 ... z1ncols /* values of row 1 */

z21 z22 z23 ... z2ncols /* values of row 2 */

.
.
.

znrows1 znrows2 znrows3 ... znrowsncols /* values of last row*/

Example

Following is an example file in the GRASS ASCII grid file format:

north: 3451250
south: 3438850
east: 298960
west: 290860
rows: 10
cols: 5
0 1 1 0 1
1 1 0 0 1
.
.
0 0 1 1 0

External Links

• GRASS GIS at OSGeo