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NAME - Create points along input lines in new vector with 2 layers.


vector, geometry

SYNOPSIS help [-nvit] input=name output=name [type=string[,string,...]] [llayer=integer] [dmax=float] [--overwrite] [--verbose] [--quiet]


Write line nodes
Write line vertices
Interpolate points between line vertices
Do not create attribute table
Allow output files to overwrite existing files
Verbose module output
Quiet module output


Input vector map containing lines
Output vector map where points will be written
Feature type
Options: point,line,boundary,centroid,area
Default: point,line,boundary,centroid
Layer number
Line layer
Default: 1
Maximum distance between points in map units
Default: 100

DESCRIPTION creates points along input lines. The output is a vector with 2 layers. Layer 1 holds the category and attributes of the input lines; all points created along the same line have the same category, equal to the category of that line. In layer 2 each point has it's unique category; other attributes stored in layer 2 are lcat - the category of the input line and along - the distance from line's start.


The dmax parameter is the maximum limit but not an exact distance. To place points with exact distance from the beginning of the vector line the user should use v.segment.

The type parameter is used to control which input vector geometry types to convert into points. Some caveats to consider about this parameter:

The -v flag is used to digitize points that fall on the line's vertices only. dmax is ignored in this case.

If the -i flag is used in conjunction with the -v flag, will digitize points on the line vertices, as well as interpolate points between line vertices using dmax as the maximum allowable spacing.

To get points created for the beginning, middle and end only, use the -i switch and set dmax so that:

    (length of input line / 2) <= dmax <= length of input line

So if dmax is between 0.5x and 1.0x the line length, you will always get points created at exactly the beginning, middle and end of the input line.


In this example, the 't_powerlines' vector lines map in the Spearfish 6 location is used to create points along the input lines: in=t_powerlines out=t_powerlines_points dmax=120
d.vect t_powerlines_points


v.segment, v.split,,


Radim Blazek

Last changed: $Date: 2014-03-10 10:03:37 -0700 (Mon, 10 Mar 2014) $

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