<

Other ASCII files

[ LINES ]   [ POINTS ]   [ POINT2D ]   [ SAMPLE ]   [ GRIDREG ]   [ TABLE ]   [ TEXT ]   [ POLYGONS ]   [ NETWORK ]   [ NETWORK_OBJECTS ]


GRIDREG

GRIDREG files type are used for rectangular grids of digital terrain models ( DTM), represented by matrices with points equally distributed on the surface, with real values normally computed by mathematical models .(see figure below).

The first line in the file is the keyword GRIDREG. This line starts the identification section, which has to be present. The GRIDREG entity must have the information section and has to have the keyword GRIDDEF followed by six parameters, they are all mandatory and are separated by blanks, in the following order:

  • Number of columns in the regular grid.
  • Number of lines in the regular grid.
  • Longitude or x coordinate, for the grid left upper corner.
  • Latitude or y coordinate, for the grid left upper corner.
  • Horizontal and Vertical spacing among grid nodes (only in meters).
  • The value attributed to the grid nodes, where the real value is unknown (nodata_value).

Notice that the only mandatory line in the information section in an ASCII file for the GRIDREG entity, is a line that has the keyword GRIDDEF. Following the information section, which is ended by the keyword INFO_END, starts the data lines for the regular grid. These values are separated by a blank. The sequence END indicates the end of the data section in the file.

The general format for the ASCII file for the GRIDREG entity is presented in the following example:

GRIDREG
GRIDREG
INFO
//Regular Grid for the Numerical Modeling
//ASCII file generated by the SPRING system
//Project: Brasilia2 - Information Layer: MNT_ISO_PTO2
//Category: Altimetry  - Model: DIGITALMODEL
DATUM	SAD69, 6378160.000000, 0.003353, 0.000000, 0.000000, 0.000000
PROJECTION	UTM/SAD69, 1, 0.000000, -0.785398, 0.000000, 0.000000
BOX	181990.505000, 8241707.402000, 202790.505000, 8262907.402000
UNITS Meters
SCALE	100000.000000
//Format GRIDDEF  <ncols>  <nlins>  <X1>  <Y2>  <resX>  <resY>  <nodatavalue>
GRIDDEF	6  7  304609.700  7412136.100  100.0000  100.0000  1464.489990
INFO_END
 732.697510 725.805359 725.201355 730.784546 737.400208 744.187317
 723.768005 718.760559 720.368652 726.018494 732.345947 739.057983
 715.368896 712.596375 715.714478 721.385315 727.419312 733.943237
 707.783142 707.184570 711.255920 716.864746 722.693604 728.930481
 701.451294 702.634827 707.320068 712.724121 718.245972 724.117554
 696.625305 698.823914 703.790222 709.130371 714.377197 719.776978
 692.684082 695.357239 700.353760 705.698486 710.959412 716.188171
END

A rectangular grid, represented by an ASCII file, as shown in the example above, might be a component of the same IL, from the numerical model, storing also the samples (contour lines and/or spot heights), triangular grid and output contour lines.

NOTE: When exporting a numerical IL with rectangular grid entity types, the option Grid Reg. in the " Exporting" window, the GRIDREG file is created. When exporting, by default, the file name extension is "spr", with the "_GRR" suffix added to the IL's name, that is, *_GRR.spr. However, for importing, the file should have only the "spr" extension, in case the file was created in a different system.


About the ASCII format

See about Importing/Exporting in the SPRING


Other ASCII files
[ LINES ]   [ POINTS ]   [ POINT2D ]   [ SAMPLE ]   [ GRIDREG ]   [ TABLE ]   [ TEXT ]   [ POLYGONS ]   [ NETWORK ]   [ NETWORK_OBJECTS ]


See also:
How to IMPORT data?
How to IMPORT data from the SGI?
How to IMPORT GRIB images?
How to EXPORT data?