mbstripNaN
Section:  MB-System 5.0  (1)
Updated:  3 June 2013 
Index


 
NAME

mbstripNaN - filter to remove NaN nodes

 
VERSION

Version 5.0

 
SYNOPSIS

mbstripNaN

 
DESCRIPTION

mbstripNaN is a utility for removing NaN nodes that are produced
by the GMT utilities grd2xyz and blockmean with the -bo
option.  The standard output
of mbstripNaN may be fed into the standard input of surface with
the -bi option.  This is used by the mbm_grd2geovrml utility in
order to spline fill areas of no data so that irregular bathymetry may
be effectively visualized using GeoVRML which has no concept of NaN.

Note that mbstripNaN works with a double precision data stream.

The code is simple.  Here it is:


  #include <stdio.h>

  #include <math.h>


  /*

   * Read double x,y,z on stdin and send to stdout all

   * triplets but ones where z == NaN

   */

  main () {

          struct node { double lon, lat, height; };


          struct node n;


          while ( ( fread(&n, 24, 1, stdin) > 0 ) ) {


                  if ( ! isnan(n.height) ) {


                          fwrite(&n, 24, 1, stdout);


                  }


          }


   }


 
EXAMPLE


This is a command that mbm_grd2geovrml constructs and executes:


  #

  # Convert grid to xyz format for filling in blank

  # areas, preprocess w/blockmean, use surface to

  # extrapolate to no data areas

  #

  grd2xyz -bo Samp_OregonMarginI_bath.grd | blockmean \

    -bi -bo -V -I0.00336363636363635/0.00134545454545457 \

    -R-125.2/-124.867/45/45.1332 | mbstripNaN | surface \

    -bi -I0.00336363636363635/0.00134545454545457 \

    -S0.333312 -T0.35 -GTmp_OregonMarginI_bath.grd -V \

    -R-125.2/-124.867/45/45.1332


 
SEE ALSO


grd2xyz(1),
blockmean(1),
surface(1),
mbm_grd2geovrml(1)



 
BUGS


How many bugs can there be in an 8 line program?



 
Index

NAME

VERSION

SYNOPSIS

DESCRIPTION

EXAMPLE

SEE ALSO

BUGS

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