r.to.vect.lines - GRASS GIS manual

NAME

r.to.vect.lines - Convert raster rows to vector lines.

KEYWORDS

SYNOPSIS

r.to.vect.lines

r.to.vect.lines --help

r.to.vect.lines [-v] input=name output=name [skip=integer] [--overwrite] [--help] [--verbose] [--quiet] [--ui]

Flags:

-v: Sample vertically (default is to sample horizontally)
--overwrite: Allow output files to overwrite existing files
--help: Print usage summary
--verbose: Verbose module output
--quiet: Quiet module output
--ui: Force launching GUI dialog

Parameters:

input=name [required]: Name of input raster map
output=name [required]: Name for output vector map
skip=integer: Sample every Nth grid row; Options: 1-100000; Default: 10

NOTES
EXAMPLE
SEE ALSO
AUTHOR

NOTES

Extracts rows from a raster map as 3D vector lines.

Reads a raster map, writes to a vector map.

Doesn't check if output map already exists. (fixme)

The category given to the line refers to the row number. (starting with category 0!)

Nulls within a row are skipped, so holes will be filled by a straight line. (fixme) Nulls at the ends of lines are not included in the output line.

Nulls are not handled very well and may sneak through as very negative numbers. (fixme)

EXAMPLE

Display a wiggle plot in NVIZ:
(Spearfish dataset)

g.region raster=elevation.dem
r.to.vect.lines.py in=elevation.dem out=wiggle_lines
eval `v.info -g wiggle_lines`
r.mapcalc "floor = $bottom"
nviz elev=floor vector=wiggle_lines

# alternative
m.nviz.image elevation_map=floor vline=wiggle_lines resolution_fine=1 \
  zexag=20 out=wiggle.png perspective=5

AUTHOR

Hamish Bowman
Dept. of Geology
University of Otago
Dunedin, New Zealand

SOURCE CODE

Available at: r.to.vect.lines source code (history)