DESCRIPTION

This module will print out distance and attributes to points/lines along profiling line. Distance is calculated from first profiling line coordinate pair or from the beginning of vector line (use "Line directions" feature in gis.m to see distance calculation direction). Output can go to file or stdout. Output file will be overwritten without warning. Buffer (tolerance) parameter sets how far point can be located from profiling line and still be included in output data set. Output map option can be used to visualy check which points are profiled. Buffer (tolerance) setting does not affect lines. Lines are sampled at their crossing point with profiling line. By default Z values are printed if input vector is a 3D map. It can be disabled with -z flag. Profiling line can be provided as N,E coordinate pairs or can come from input vector map. As currently profiling line must be single line, one should use profile_where parameter to select single line from profile input map if it contains multiple features.

NOTE

Currently module can profile only points and lines (including 3D ones). Areas and other complex features are not supported. If one can provide reasonable examples how area sampling should work and why it's important, area (or any other feature type) sampling can be added.

EXAMPLES

Get point values and distance from the city and save into file for later usage. Will use ; as delimiter and three numbers after decimal separator for distance. Output file will contain data for all points, that are within 100m range to profiling line. 
v.profile input=archsites@PERMANENT map_output=profiling_line buffer=100 \
          east_north=591518.55,4925722.38,592110.14,4920989.67 \
	  out_file=/home/user/archsites.distance dp=3 fs=';'

# Now let's see the output:
$cat archsites.distance
Number;Distance;cat;str1
1;446.958;24;"Hanson Ranch"
2;1386.149;11;"No Name"
3;2754.872;2;"No Name"
4;4559.578;13;"No Name"

Create river valley crossection and provide river marker: 

# Take elevation samples
r.profile input=elevation.dem@PERMANENT output=/home/user/elevation.profile \
  profile=600570.27364,4920613.41838,600348.034348,4920840.38617
# Now get distance to place where river marker should be set
v.profile input=streams@PERMANENT out_file=/home/user/river.profile \
  east_north=600570.27364,4920613.41838,600348.034348,4920840.38617

BUGS

Strings are enclosed in double quotes ", still quotes within string are not escaped.

Vector CAT values are not outputed. Only way how to get CAT value is from attribute table.

SEE ALSO

r.profile

AUTHOR

Maris Nartiss

Last changed: $Date$