Provided by: gmt-common_5.4.5+dfsg-1_all bug

NAME

       gmtinfo - Return information about data tables

SYNOPSIS

       gmtinfo [ table ] [  -Aa|f|s ] [  -C ] [  -D[dx[/dy]] ] [  -EL|l|H|hcol ] [  -F[i|d|t] ] [
       -I[p|f|s]dx[/dy[/dz...] ] [  -L ] [   -S[x][y]  ]  [   -Tdz[+ccol]  ]  [   -V[level]  ]  [
       -bibinary  ] [ -dinodata ] [ -eregexp ] [ -fflags ] [ -ggaps ] [ -hheaders ] [ -iflags ] [
       -oflags ] [ -r ] [ -:[i|o] ]

       Note: No space is allowed between the option flag and the associated arguments.

DESCRIPTION

       gmtinfo reads its standard input [or from files] and finds the extreme values in  each  of
       the  columns  reported as slash-separated min/max pairs. It recognizes NaNs and will print
       warnings if the number of columns vary from record to record. The pairs can be split  into
       two  separate  columns  by  using  the -C option.  As another option, gmtinfo can find the
       extent of data in the first two columns rounded up and down to the nearest multiple of the
       supplied increments given by -I. Such output will be in the text form -Rw/e/s/n, which can
       be used directly on the command line for other modules (hence only dx and dy are  needed).
       If  -C  is combined with -I then the output will be in column form and rounded up/down for
       as many columns as there are increments provided in -I. A similar option (-T) will provide
       a -Tzmin/zmax/dz string for makecpt.

REQUIRED ARGUMENTS

       None.

OPTIONAL ARGUMENTS

       table  One  or  more  ASCII (or binary, see -bi[ncols][type]) data table file(s) holding a
              number of data columns. If no tables are given then we read from standard input.

       -Aa|f|s
              Specify how the range should be reported. Choose -Aa for the  range  of  all  files
              combined,  -Af  to report the range for each file separately, and -As to report the
              range for each segment (in multisegment files) separately. [Default is -Aa].

       -C     Report the min/max values per column in separate columns  [Default  uses  <min/max>
              format].  When  used, users may also use -o to limit which output columns should be
              reported [all].

       -D     Modifies results obtained by -I by shifting the region to  better  align  with  the
              center  of  the  data.   Optionally,  append  granularity  for  this shift [Default
              performs an exact shift].

       -EL|l|H|hcol
              Returns the record whose column col contains the minimum (l) or maximum (h)  value.
              Upper  case (L|H) works on absolute value of the data. In case of multiple matches,
              only the first record is returned. If col is not specified we default to  the  last
              column in the data.

       -F[i|d|t] ]
              Returns  the  counts of various records depending on the appended mode: i returns a
              single record with the total number  of  tables,  segments,  data  records,  header
              records,  and overall records.  In contrast, d returns information for each segment
              in the virtual data set: tbl_number, seg_number,  n_rows,  start_rec,  stop_rec.  t
              does  the  same but honors the input table organization and thus resets seg_number,
              start_rec, stop_rec at the start of each new table.

       -I[p|f|s]dx[/dy[/dz...]
              Report the min/max of the first n columns to the nearest multiple of  the  provided
              increments  (separate  the n increments by slashes), and output results in the form
              -Rw/e/s/n (unless -C is set). If only one increment is given we also use it for the
              second  column (for backwards compatibility). To override this behavior, use -Ipdx.
              If the input x- and y-coordinates all have the same phase shift relative to the  dx
              and dy increments then we use those phase shifts in determining the region, and you
              may use  -r  to  switch  from  gridline-registration  to  pixel-registration.   For
              irregular  data  both  phase  shifts  are  set  to  0  and  the -r is ignored.  Use
              -Ifdx[/dy] to report an extended region  optimized  to  give  grid  dimensions  for
              fastest  results  in  programs  using  FFTs.   Use -Isdx[/dy] to report an extended
              region optimized to give grid dimensions  for  fastest  results  in  programs  like
              surface.   If dx is given as - then the actual min/max of the input is given in the
              -R string.

       -L     Determines common limits across tables (-Af) or segments (-As).  If used with -I it
              will round inwards so that the resulting bounds lie within the actual data domain.

       -S[x][y]
              Add  extra  space  for  error  bars.  Useful together with -I option and when later
              plotting with psxy -E. -Sx leaves space for horizontal error bars using the  values
              in  third  (2) column. -Sy leaves space for vertical error bars using the values in
              fourth (3) column. -S or -Sxy leaves space for both error bars using the values  in
              third and fourth (2 and 3) columns.

       -Tdz[+ccol]
              Report  the  min/max  of  the first (0'th) column to the nearest multiple of dz and
              output this as the string -Tzmin/zmax/dz. To  use  another  column,  append  +ccol.
              Cannot be used together with -I.

       -V[level] (more ...)
              Select verbosity level [c].

       -bi[ncols][t] (more ...)
              Select native binary input. [Default is 2 input columns].

       -dinodata (more ...)
              Replace input columns that equal nodata with NaN.

       -e[~]"pattern" | -e[~]/regexp/[i] (more ...)
              Only accept data records that match the given pattern.

       -f[i|o]colinfo (more ...)
              Specify data types of input and/or output columns.

       -g[a]x|y|d|X|Y|D|[col]z[+|-]gap[u] (more ...)
              Determine data gaps and line breaks.

       -h[i|o][n][+c][+d][+rremark][+rtitle] (more ...)
              Skip or produce header record(s).

       -icols[+l][+sscale][+ooffset][,...] (more ...)
              Select input columns and transformations (0 is first column).

       -ocols[,...] (more ...)
              Select output columns (0 is first column).

       -r (more ...)
              Set pixel node registration [gridline].

       -:[i|o] (more ...)
              Swap 1st and 2nd column on input and/or output.

       -^ or just -
              Print a short message about the syntax of the command, then exits (NOTE: on Windows
              just use -).

       -+ or just +
              Print  an  extensive  usage  (help)  message,  including  the  explanation  of  any
              module-specific option (but not the GMT common options), then exits.

       -? or no arguments
              Print  a  complete  usage (help) message, including the explanation of all options,
              then exits.

ASCII FORMAT PRECISION

       The ASCII output formats of numerical data are controlled by parameters in  your  gmt.conf
       file.  Longitude  and latitude are formatted according to FORMAT_GEO_OUT, absolute time is
       under the control of FORMAT_DATE_OUT and FORMAT_CLOCK_OUT, whereas general floating  point
       values are formatted according to FORMAT_FLOAT_OUT. Be aware that the format in effect can
       lead to loss of precision in ASCII output, which can lead to various problems  downstream.
       If  you find the output is not written with enough precision, consider switching to binary
       output (-bo if available) or specify more decimals using the FORMAT_FLOAT_OUT setting.

EXAMPLES

       To find the extreme values in the file ship_gravity.xygd:

              gmt info 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  but  shifted  to
       within 1 unit of the data center, and use this region to draw a line using psxy, run

              gmt psxy `gmt info -I5 -D1 track.xy` track.xy -Jx1 -B5 -P > track.ps

       To  find  the min and max values for each of the first 4 columns, but rounded to integers,
       and return the result individually for each data file, use

              gmt info profile_*.txt -C -I1/1/1/1

       Given seven profiles with different start and stop positions, we want to find a  range  of
       positions, with increment of 5, that are common to all the profiles.  We use

              gmt info profile_[123567].txt -L -I5

       The  file  magprofs.txt  contains  a  number  of magnetic profiles stored as separate data
       segments.  We need to know how many segments there are and use

              gmt info magprofs.txt -Fi

BUGS

       The -I option does not yet work properly with time series data (e.g.,  -f0T).  Thus,  such
       variable  intervals as months and years are not calculated. Instead, specify your interval
       in the same units as the current setting of TIME_UNIT.

SEE ALSO

       gmt, gmtconvert, psxy

COPYRIGHT

       2019, P. Wessel, W. H. F. Smith, R. Scharroo, J. Luis, and F. Wobbe