GSHHS(1gmt)
NAME
gshhs - Extract ASCII listings from binary GSHHS or WDBII data files
SYNOPSIS
gshhs binaryfile.b [ -Iid ] [ -L ] [ -M ] > asciifile.txt
DESCRIPTION
gshhs reads the binary coastline (GSHHS) or political boundary or river
(WDBII) files and extracts an ASCII listing. It automatically handles
byte-swabbing between different architectures. Optionally, only segment header info can be displayed. The header info has the format ID
npoints hierarchical-level source area f_area west east south north
container ancestor, where hierarchical levels for coastline polygons go
from 1 (shoreline) to 4 (lake inside island inside lake inside land).
Source is either W (World Vector Shoreline) or C (CIA World Data Bank
II); lower case is used if a lake is a river-lake. The west east south
north is the enclosing rectangle, area is the polygon area in km^2
while f_area is the actual area of the ancestor polygon, container is
the ID of the polygon that contains this polygon (-1 if none), and
ancestor is the ID of the polygon in the full resolution set that was
reduced to yield this polygon (-1 if full resolution). For line data
the header is simply ID npoints hierarchical-level source west east
south north
- binaryfile.b
- GSHHS or WDBII binary data file as distributed with the GSHHS data supplement. Any of the 5 standard resolutions (full, high, intermediate, low, crude) can be used.
- -I Only output information for the polygon that matches id [default
- outputs all polygons].
- -L Only output a listing of polygon or line segment headers
- [default outputs headers and data records].
- -M Start all header records with the GMT multiple segment indicator
- '>' [Default uses P for polygons and L for lines].
EXAMPLES
To convert the entire intermediate GSHHS binary data to ASCII, run
gshhs gshhs_i.b > gshhs_i.txt
To only get a listing of the headers for the river data set at full
resolution, try
gshhs wdb_rivers_f.b -L > riverlisting.txt
BUGS
While the GSHHS data is organized as a set of closed polygons, the
rivers and boundary data are just a set of line segments in no particular order. Thus, it is not possible to extract information pertaining
to just one river or one country.
SEE ALSO
- GMT(1), gshhs_dp(1) gshhstograss(1)