NAME

       grdinfo - Get information about the contents of a 2-D grd file

SYNOPSIS

       grdinfo  grdfiles  [  -C ] [ -F ] [ -Idx[/dy] ][ -L1 ] [ -L2 ] [ -M ] [
       -Tdz ] [ -V ] [ -f[i|o]colinfo ]

DESCRIPTION

       grdinfo reads a 2-D binary grd file and reports various statistics  for
       the  (x,y,z)  data  in the grdfile. The output information contains the
       minimum/maximum values for x, y, and z, where the min/max of  z  occur,
       the  x- and y-increments, and the number of x and y nodes, and [option-
       ally] the mean, standard deviation, and/or the median, L1 scale  of  z,
       and number of nodes set to NaN.

       grdfile
              The name of one or several 2-D grd files.

OPTIONS

       No space between the option flag and the associated arguments.

       -C     Formats  the report using tab-separated fields on a single line.
              The output is w e s n z0 z1 dx dy nx ny [ x0 y0 x1 y1  ]  [  med
              scale  ] [ mean std rms] [n_nan].  The data in brackets are out-
              put only if the corresponding options -M, -L1, -L2, and  -M  are
              used, respectively.  If the -I option is used, the output format
              is instead NF w e s n z0 z1, where NF is  the  total  number  of
              grids read and w e s n are rounded off (see -I).

       -F     Report  grid  domain  and x/y-increments in world mapping format
              [Default is generic].  Does not apply to the -C option.

       -I

       Report the min/max of the region to the nearest multiple of dx and dy,
              and output this in the form -Rw/e/s/n (unless -C is  set).   -L1
              Report  median  and  L1  scale  of z (L1 scale = 1.4826 * Median
              Absolute Deviation (MAD)).

       -L2    Report mean and standard deviation of z.

       -M     Find and report the location of min/max z-values, and count  and
              report the number of nodes set to NaN, if any.

       -T     Determine min and max z-value, round off to multiples of dz, and
              report as the text string -Tzmin/zmax/dz for use by makecpt.

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

       -f     Special  formatting  of  input  and output columns (time or geo-
              graphical data) Specify i(nput) or  o(utput)  [Default  is  both
              input  and output].  Give one or more columns (or column ranges)
              separated by commas.  Append T (Absolute calendar time), t (time
              relative  to  chosen TIME_EPOCH), x (longitude), y (latitude), g
              (geographic coordinate), or f (floating point) to each column or
              column range item.

EXAMPLES

       To   obtain   all   the   information   about  the  data  set  in  file
       hawaii_topo.grd:

       grdinfo -L1 -L2 -M hawaii_topo.grd

SEE ALSO

       gmt(l), grd2cpt(l), grd2xyz(l), grdedit(l)



GMT4.0                            1 Oct 2004                        GRDINFO(l)