ASCII2DTM: ASCII2DTM

In rFUSION: Interface to FUSION

Description

ASCII2DTM converts raster data stored in ESRI ASCII raster format into a PLANS format data file. Data in the input ASCII raster file can represent a surface or raster data. ASCII2DTM converts areas containing NODATA values into areas with negative elevation values in the output data file.

Usage

ASCII2DTM(
  fusion.path = "C:/FUSION/",
  surfacefile,
  xyunits,
  zunits,
  coordsys,
  zone,
  horizdatum,
  vertdatum,
  Gridfile,
  switches = NULL
)

Arguments

fusion.path	Character. By default: C:/FUSION/. Path where the program FUSION is installed.
surfacefile	Character. Name for output canopy surface file (stored in PLANS DTM format with .dtm extension).
xyunits	Character. Units for LIDAR data XY: M - for meters. F - for feet.
zunits	Character. Units for LIDAR data elevations: M - for meters. F - for feet.
coordsys	Numeric. Coordinate system for the canopy model: 0 - for unknown. 1 - for UTM. 2 - for state plane.
zone	Numeric. Coordinate system zone for the canopy model (0 for unknown).
horizdatum	Numeric. Horizontal datum for the canopy model. 0 - for unknown. 1 - for NAD27. 2 -for NAD83.
vertdatum	Numeric. LIDAR data file name or template or name of a text file containing a list of file names (list file must have .txt extension). 0 - for unknown. 1 - for NGVD29. 2 - for NAVD88. 3 - for GRS80.
Gridfile	Character. Name of the ESRI ASCII raster file containing surface data.
switches	Character. NULL as default. To insert a switch, it must have a '/' before of the names. If you want to insert two or more switches, they must be separated by an empty space. When a # is displayed, should be replaced by the desired value (numeric). /multiplier:# - Multiply all data values in the input surface by the constant. /offset:# - Add the constant to all data values in the input surface. The constant can be negative. /nan - Create FUSION index files for the output file.

Details

ASCII2DTM recognizes both the (xllcorner, yllcorner) and (xllcenter, yllcenter) methods for specifying the location of the raster data. The PLANS DTM format used in FUSION always assumes that the data point (grid point) in the lower left corner is the model origin and adjusts the location of the raster data accordingly.
ASCII2DTM examines the ASCII raster file to determine whether the elevation values are integers or floating point numbers. It creates the PLANS DTM file using either integer or 4-byte floating point values for the elevations.
ASCII2DTM always assumes that the data stored in ASCII raster format is interpreted as a raster. That is, the value is representative of the entire grid cell. For data that represent a surface where the values are actually elevations at specific points, the origin of the DTM file is set to the center of the lower left cell in the grid.
If you receive surface data in ESRI’s GRID format it is possible to use GDAL (http://www.gdal.org/) to convert the GRID data into ASCII raster format. Refer to Appendix D: Building multi-processor workflows using AreaProcessor for more details.
If you are using DTM2ASCII to convert data from the PLANS DTM format into ASCII raster format, you should always use the /raster switch in DTM2ASCII to ensure that you can convert the data back to the PLANS DTM format using ASCII2DTM.

Value

No return value. This function return the command prompt running the FUSION command

References

McGaughey, R.J. FUSION/LDV: Software for LIDAR Data Analysis and Visualization. 2021.

Examples

surfacefile<-'Z:/dtmfile.dtm'
Gridfile<- 'Z:/gridfile.asc'
ASCII2DTM(surfacefile = surfacefile,xyunits = 'M',zunits = 'M',
          coordsys = 1,zone = 0, horizdatum = 0, vertdatum = 0,
                    Gridfile = Gridfile, switches = NULL)

rFUSION documentation built on March 17, 2021, 5:07 p.m.