NAME

       gshhg_dp - Line reduction using the Douglas-Peucker algorithm

SYNOPSIS

       gshhg_dp input.b tolerance output.b [-v]

DESCRIPTION

       gshhg_dp  reads the binary coastline (GSHHS) or political boundary or river (WDBII) files and and reduces
       the complexity of the line by applying the Douglas-Peucker algorithm.   It  automatically  handles  byte-
       swabbing between different architectures.

       input.b
              GSHHS  or  WDBII  binary  data  file  as distributed with the GSHHG data supplement.  Any of the 5
              standard resolutions (full, high, intermediate, low, crude) can be used.

       tolerance
              tolerance is maximum mismatch in km.  The larger the value the more reduction will take place.

       output.b
              The reducted data set.

OPTIONS

       -v     Reports progress and statistics while running.

EXAMPLES

       To simplify the full GSHHS data set with a custom tolerance of 2 km, try

       gshhg_dp gshhs_f.b 2 gshhs_2km.b

REFERENCES

       Douglas, D. H., and T. K. Peucker, Algorithms for the reduction of  the  number  of  points  required  to
       represent a digitized line of its caricature, Can. Cartogr., 10, 112-122, 1973.

AUTHOR

       This  implementation of the D-P algorithm has been kindly provided by Dr. Gary J. Robinson, Environmental
       Systems Science Centre, University of Reading, Reading, UK (gazza@mail.nerc-essc.ac.uk);  his  subroutine
       forms the basis for this program.

SEE ALSO

       GMT(1), gshhg(1), gshhgtograss(1)