GRASS GIS manual: r.in.poly

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NAME

r.in.poly - Creates raster maps from ASCII polygon/line/point data files.

KEYWORDS

raster, import

SYNOPSIS

r.in.poly
r.in.poly help
r.in.poly input=name output=name [title="phrase"] [rows=integer] [--overwrite] [--verbose] [--quiet]

Flags:

--overwrite: Allow output files to overwrite existing files
--verbose: Verbose module output
--quiet: Quiet module output

Parameters:

input=name: Name of input file; or "-" to read from stdin
output=name: Name for output raster map
title="phrase": Title for resultant raster map
rows=integer: Number of rows to hold in memory; Default: 4096

DESCRIPTION

r.in.poly allows the creation of GRASS binary raster maps from ASCII files in the current directory containing polygon, linear, and point features.

The input file is an ASCII text file containing the polygon, linear, and point feature definitions. The format of this file is described in the INPUT FORMAT section below.

The number of raster rows to hold in memory is per default 4096. This parameter allows users with less memory (or more) on their system to control how much memory r.in.poly uses. Usually the default value is fine.

NOTES

The data will be imported using the current region settings to set the new raster map's bounds and resolution. Any features falling outside the current region will be cropped. The region settings are contolled with the g.region module.

The format is a simplified version of the standard GRASS vector ASCII format used by v.in.ascii.

Polygons are filled, i.e. they define an area.

Input Format

The input format for the input file consists of sections describing either polygonal areas, linear features, or point features. The basic format is:

A                      <for polygonal areas>
    easting northing
    .
    .
    .
=   cat# label
L                      <for linear features>
    easting northing
    .
    .
    .
=   cat# label
P                      <for single cell point features>
    easting northing
=   cat# label

The A signals the beginning of a filled polygon. It must appear in the first column. The L signals the beginning of a linear feature. It also must appear in the first column. The P signals the beginning of a single cell point feature. Again, it must appear in the first column. The coordinates of the vertices of the polygon, or the coordinates defining the linear or point feature follow and must have a space in the first column and at least one space between the easting and the northing. To give meaning to the features, the "=" indicates that the feature currently being processed has category value cat# (which must be an integer) and a label (which may be more than one word, or which may be omitted).

EXAMPLE

An area described by four points:

A
  591316.80   4926455.50
  591410.25   4926482.40
  591434.60   4926393.60
  591341.20   4926368.70
= 42 stadium

AUTHOR

Michael Shapiro, U.S.Army Construction Engineering Research Laboratory

Last changed: $Date: 2008-05-21 11:40:03 -0700 (Wed, 21 May 2008) $

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