grdedit(1gmt) [debian man page]

GRDEDIT(l)																GRDEDIT(l)

NAME

       grdedit - Modifying the header in a 2-D grdfile

SYNOPSIS

       grdedit grdfile [ -A ] [ -Dxunit/yunit/zunit/scale/offset/title/remark ] [ -Rwest/east/south/north[r] ] [ -S ] [ -V ]

DESCRIPTION

       grdedit	reads  the  header  information  in a binary 2-D grdfile and replaces the information with values provided on the command line [if
       any]. As an option, global, geographical grids (with 360 degrees longitude range) can be rotated in the east-west direction.  grdedit  only
       operates on files containing a grdheader.
	       No space between the option flag and the associated arguments. Use upper case for the option flags and lower case for modifiers.

       grdfile
	      Name of the 2-D grdfile to modify

OPTIONS

       -A     If necessary, adjust the file's x_inc, y_inc to be compatible with its domain (or a new domain set with -R).  Older gridfiles (i.e.,
	      created prior to GMT 3.1) often had excessive slop in' x_inc, y_inc and an adjustment is necessary. Newer  files	are  created  cor-
	      rectly.

       -D     Give  new values for xunit, yunit, zunit, scale, offset, title, and remark.  To leave some of the values untouched, specify = as the
	      new value.

       -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.  The new w/e/s/n values will
	      replace those in the grid, and the x_inc, y_inc values are adjusted, if necessary.

       -S     For global, geographical grids only. Grid values will be shifted laterally according to the new borders given in -R.

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

EXAMPLES

       Let us assume the file data.grd covers the area 300/310/10/30. We want to change the boundaries from geodetic longitudes to geographic  and
       put a new title in the header. We accomplish this by

       grdedit data.grd -R-60/-50/10/30 -D=/=/=/=/=/"Gravity Anomalies"/=

       The grid world.grd has the limits 0/360/-72/72. To shift the data so that the limits would be -180/180/-72/72, use

       grdedit world.grd -R-180/180/-72/72 -S

       The file junk.grd was created prior to GMT 3.1 with incompatible -R and -I arguments. To reset the x- and y-increments we run

       grdedit junk.grd -A

SEE ALSO

       gmt(1gmt), grd2xyz(1gmt), xyz2grd(1gmt)

								    1 Jan 2004								GRDEDIT(l)

GRD2XYZ(l)																GRD2XYZ(l)

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 ta-
	      ble 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)