NAME

     grd2xyz - Converting a grdfile to an ASCII or binary table


SYNOPSIS

     grd2xyz grdfile [ -H[nrec] ] [ -Rwest/east/south/north[r]  [
     -S ] [ -Z[flags] ] [ -bo[s] ]


DESCRIPTION

     grd2xyz reads a binary  2-D  grdfile  and  writes  out  xyz-
     triplets  in  ASCII  [or  binary] format to standard output.
     Modify the precision of the ASCII output format  by  editing
     the  D_FORMAT parameter in your .gmtdefaults file, or choose
     binary output using single or double precision storage.   As
     an  option  you  may  output z-values without the (x,y) in a
     number of formats, see -Z below.

     grdfile
          The 2-D binary file to be converted.


OPTIONS

     -H   Output 1 header record  based  on  information  in  the
          grdfile  header.  Ignored if binary output is selected.
          [Default is no header].

     -R   west, east, south, and  north  specify  the  Region  of
          interest.  To specify boundaries in degrees and minutes
          [and seconds], use the dd:mm[:ss] format.  Append r  if
          lower  left  and  upper right map coordinates are given
          instead of wesn.

     -S   Suppress output for  nodes  whose  z-value  equals  NaN
          [Default outputs all nodes].

     -Z   Write a 1-column ASCII [or binary] table.  Output  will
          be  organized  according to the specified ordering con-
          vention contained in flags.  If data should be  written
          by  rows, make flags start with T(op) if first row is y
          = ymax or B(ottom) if first row is  y  =  ymin.   Then,
          append  L  or  R  to indicate that first element should
          start at left or right end of row.  Likewise for column
          formats:  start  with  L or R to position first column,
          and then append T or B to position first element  in  a
          row.   For  gridline  registered  grids:   If  grid  is
          periodic in x but the outcoming data should not contain
          the (redundant) column at x = xmax, append x.  For grid
          periodic in y, skip writing the redundant row  at  y  =
          ymax  by  appending  y.   If the byte-order needs to be
          swapped, append w.  Select one of  several  data  types
          (all binary except a):

               a  ASCII representation
               c  signed 1-byte character
               u  unsigned 1-byte character
               h  short 2-byte integer
               i  4-byte integer
               l  long (4- or 8-byte) integer
               f  4-byte floating point single precision
               d  8-byte floating point double precision

          Default  format  is  scanline  orientation   of   ASCII
          numbers:  -ZTLa.  Note that -Z only applies to 1-column
          output.

     -bo  Selects binary output.  Append s for  single  precision
          [Default  is  double].  This option only applies to xyz
          output; see -Z for z table output.


EXAMPLES

     To edit individual values in the  5'  by  5'  hawaii_grv.grd
     file, try

     grd2xyz hawaii_grv.grd > hawaii_grv.xyz

     To write a single precision  binary  file  without  the  x,y
     positions  from  the  file raw_data.grd file, using scanline
     orientation, try

     grd2xyz raw_data.grd -ZTLf > hawaii_grv.b


SEE ALSO

     gmtdefaults(l), gmt(l), grdedit(l), xyz2grd(l)