v.parallel(1)

NAME
v.parallel - Creates parallel line to input vector lines.

KEYWORDS
vector, geometry, buffer, line

SYNOPSIS
v.parallel
v.parallel --help
v.parallel [-rb] input=name [layer=string] output=name distance=float [minordistance=float] [angle=float] side=string [tolerance=float] [--overwrite] [--help] [--verbose] [--quiet] [--ui]

  Flags:

-r
    Make outside corners round

-b
    Create buffer-like parallel lines

--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 vector map
    Or data source for direct OGR access

layer=string
    Layer number or name (’-1’ for all layers)
    A single vector map can be connected to multiple database tables. This number determines which table to use. When used with direct OGR access this is the layer name.
    Default: -1

output=name [required]
    Name for output vector map

distance=float [required]
    Offset along major axis in map units
    Options: 0-100000000

minordistance=float
    Offset along minor axis in map units
    Options: 0-100000000

angle=float
    Angle of major axis in degrees
    Default: 0

side=string [required]
    Side
    Options: left, right, both
    Default: right
    left: Parallel line is on the left
    right: Parallel line is on the right
    both: Parallel lines on both sides

tolerance=float
    Tolerance of arc polylines in map units
    Options: 0-100000000

DESCRIPTION
v.parallel creates parallel lines to the input vector lines which can be used as half-buffers.

NOTES
Usage of -b flag will overrule the side parameter.

KNOWN ISSUES
There is a problem with side-offset parallel line generation for inside corners. To avoid this problem, the -b flag might be used.

SEE ALSO
v.buffer

AUTHORS
Radim Blazek
Rewritten by Rosen Matev (with support through the Google Summer of Code program 2008)

SOURCE CODE

Available at: v.parallel source code (history)

Accessed: Saturday May 09 13:02:33 2026

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