NAME

       grd2xyz - Converting a grdfile to an ASCII or binary table

SYNOPSIS

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

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].

       -L     Indicates that the x values are longitudes (necessary for -: to work).

       -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].
              Append r to reverse the suppression, i.e., only  output  the  nodes  whose  z-value
              equals NaN.

       -V     Selects  verbose  mode,  which  will  send progress reports to stderr [Default runs
              "silently"].

       -Z     Write a 1-column ASCII [or binary] table. Output will be organized according to the
              specified  ordering  convention  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(1gmt), gmt(1gmt), grdedit(1gmt), xyz2grd(1gmt)

                                            1 Jan 2004                                 GRD2XYZ(l)