trusty (1) minmax.1gmt.gz

NAME

       minmax - Find extreme values in data tables

SYNOPSIS

       minmax [ files] [ -C ] [ -D ] [ -H[nrec] ] [ -Idx[/dy] ] [ -L ] [ -M[flag] ] [ -: ] [ -bi[s][n] ]

DESCRIPTION

       minmax  reads  its standard input [or from files] and finds the extreme values in each of the columns. It
       recognizes NaNs and will print warnings if the number of columns vary  from  record  to  record.   As  an
       option,  minmax will find the extent of the first two columns rounded up and down to the nearest multiple
       of dx/dy. This output will be in the form -Rw/e/s/n which can be used directly in the  command  line  for
       other programs, or simply in column form.

       xyzfile
              ASCII [or binary, see -b] file(s) holding a fixed number of data columns.

OPTIONS

       -C     Report the min/max values per column in separate columns [Default uses <min/max> format]

       -D     Sets longitude discontinuity to the Dateline (-180/+180) [Default is Greenwich (0-360)].  Requires
              -L.

       -H     Input file(s) has Header record(s). Number of header  records  can  be  changed  by  editing  your
              .gmtdefaults file. If used, GMT default is 1 header record.

       -I     Report  the min/max of the first two columns to the nearest multiple of dx and dy, and output this
              in the form -Rw/e/s/n (unless -C is set).

       -L     Indicates that the x column contains longitudes, which may be periodic  in  360  degrees  [Default
              assumes no periodicity].

       -M     Multiple  segment  file(s). Segments are separated by a special record.  For ASCII files the first
              character must be flag [Default is '>'].  For binary files all fields must be NaN.

       -:     Toggles  between  (longitude,latitude)  and   (latitude,longitude)   input/output.   [Default   is
              (longitude,latitude)].  Applies to geographic coordinates only.  Only works when -I is selected.

       -bi    Selects  binary input. Append s for single precision [Default is double].  Append n for the number
              of columns in the binary file(s).  [Default is 2 input columns].

EXAMPLES

       To find the extreme values in the file ship_gravity.xygd, try

       minmax ship_gravity.xygd

       Output should look like

       ship_gravity.xygd: N = 6992 <326.125/334.684> <-28.0711/-8.6837> <-47.7/177.6> <0.6/3544.9>

       To find the extreme values in the file track.xy to the nearest 5 units and use this region to draw a line
       using psxy, try

       psxy `minmax -I5 track.xy` track.xy -Jx1 -B5 -P > track.ps

       To find the min and max values for each column, but rounded to integers, try

       minmax junkfile -C -I1

SEE ALSO

       gmt(1gmt)

                                                   1 Jan 2004                                          MINMAX(l)