xenial (1) x2sys_list.1gmt.gz

Provided by: gmt-common_5.2.1+dfsg-3build1_all bug

NAME

       x2sys_list - Extract subset from crossover data base

SYNOPSIS

       x2sys_list  column TAG [ coedbase.txt ] [ asymm_max ] [  ] [ acdhiInNtTvwxyz ] [ [list] ] [ [corrtable] ]
       [ nx_min ] [ e|i ] [ region ] [ track ] [ [level] ] [ [list] ] [ -bo<binary> ]

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

DESCRIPTION

       x2sys_list will read the crossover ASCII data base coedbase.txt (or stdin) and extract a  subset  of  the
       crossovers based on the other arguments. The output may be ASCII or binary.

REQUIRED ARGUMENTS

       -Ccolumn
              Specify  which  data  column  you  want to process. Crossovers related to this column name must be
              present in the crossover data base.

       -TTAG  Specify the x2sys TAG which tracks the attributes of this data type.

OPTIONAL ARGUMENTS

       coedbase.txt
              The name of the input ASCII crossover error data base as produced by x2sys_cross. If not given  we
              read standard input instead.

       -Aasymm_max
              Specifies  maximum  asymmetry  in the distribution of crossovers relative to the mid point in time
              (or distance, if not time is available). Asymmetry is computed as (n_right  -  n_left)/(n_right  +
              n_left), referring the the number of crossovers that falls in the left or right half of the range.
              Symmetric distributions will have values close to zero. If  specified,  we  exclude  tracks  whose
              asymmetry exceeds the specify cutoff in absolute value [1, i.e., include all].

       -E     Enhance  ASCII  output  by writing GMT segment headers with name of the two tracks and their total
              number of cross-overs [no segment headers].

       -FacdhiInNtTvwxyz
              Specify your desired output using any combination of acdhiInNtTvwxyz, in any  order.  Do  not  use
              space between the letters, and note your selection is case-sensitive. The output will be ASCII (or
              binary, -bo) columns of values. Description of codes: a  is  the  angle  (<  90)  defined  by  the
              crossing tracks, c is crossover value of chosen observation (see -C), d is distance along track, h
              is heading along track, i is the signed time interval between the visit at the  crossover  of  the
              two tracks involved, I is same as i but is unsigned, n is the names of the two tracks, N is the id
              numbers of the two tracks, t is time along track in dateTclock format (NaN if not available), T is
              elapsed time since start of track along track (NaN if not available), v is speed along track, w is
              the composite weight, x is x-coordinate (or longitude), y is y-coordinate (or latitude), and z  is
              observed  value  (see  -C)  along  track. If -S is not specified then d,h,n,N,t,T,v results in two
              output columns each: first for track one and next for track two (in lexical order of track names);
              otherwise,  they  refer to the specified track only (except for n,N which then refers to the other
              track). The sign convention for c,i  is  track  one  minus  track  two  (lexically  sorted).  Time
              intervals will be returned according to the TIME_UNIT GMT defaults setting.

       -I[list]
              Name  of  ASCII  file  with  a  list  of track names (one per record) that should be excluded from
              consideration [Default includes all tracks].

       -L[corrtable]
              Apply optimal corrections to the chosen observable. Append the correction table  to  use  [Default
              uses  the  correction table TAG_corrections.txt which is expected to reside in the $X2SYS_HOME/TAG
              directory]. For the format of this file, see x2sys_solve.

       -Nnx_min
              Only report data from pairs that generated at  least  nx_min  crossovers  between  them  [use  all
              pairs].

       -Qe|i  Append e for external crossovers or i for internal crossovers only [Default is all crossovers].

       -R[unit]west/east/south/north[/zmin/zmax][r]
              west,  east,  south, and north specify the region of interest, and you may specify them in decimal
              degrees or in [+-]dd:mm[:ss.xxx][W|E|S|N] format. Append r if  lower  left  and  upper  right  map
              coordinates  are  given instead of w/e/s/n. The two shorthands -Rg and -Rd stand for global domain
              (0/360 and -180/+180 in longitude respectively, with -90/+90 in latitude).  Alternatively for grid
              creation,  give  Rcodelon/lat/nx/ny, where code is a 2-character combination of L, C, R (for left,
              center, or right) and T, M, B for top, middle, or bottom. e.g., BL for lower left.  This indicates
              which  point  on a rectangular region the lon/lat coordinate refers to, and the grid dimensions nx
              and ny with grid spacings via -I is used  to  create  the  corresponding  region.   Alternatively,
              specify  the  name  of an existing grid file and the -R settings (and grid spacing, if applicable)
              are copied from the grid. Using -Runit expects projected (Cartesian) coordinates  compatible  with
              chosen  -J  and  we  inversely  project  to  determine  actual rectangular geographic region.  For
              perspective view (-p), optionally append /zmin/zmax.  In case of perspective view (-p), a  z-range
              (zmin,  zmax)  can  be  appended  to indicate the third dimension. This needs to be done only when
              using the -Jz option, not when using only the -p option. In the latter case a perspective view  of
              the  plane  is plotted, with no third dimension. For Cartesian data just give xmin/xmax/ymin/ymax.
              This option bases the statistics on those COE that fall inside the specified domain.

       -Strack
              Name of a single track. If given we restrict output  to  those  crossovers  involving  this  track
              [Default output is crossovers involving any track pair].

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

       -W[list]
              Name  of  ASCII  file with a list of track names and their relative weights (one track per record)
              that should be used to calculate the composite crossover weight (output code  w  above).  [Default
              sets weights to 1].

       -bo[ncols][type] (more ...)
              Select native binary output.

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

       -+ 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 options, then exits.

       --version
              Print GMT version and exit.

       --show-datadir
              Print full path to GMT share directory and exit.

EXAMPLES

       To find all the magnetic crossovers associated with the tag MGD77 from the file COE_data.txt,  restricted
       to occupy a certain region in the south Pacific, and return location, time, and crossover value, try

              gmt x2sys_list COE_data.txt -V -TMGD77 -R180/240/-60/-30 -Cmag -Fxytz > mag_coe.txt

       To  find  all the faa crossovers globally that involves track 12345678 and output time since start of the
       year, using a binary double precision format, try

              gmt x2sys_list COE_data.txt -V -TMGD77 -Cfaa -S12345678 -FTz -bod > faa_coe.b

SEE ALSO

       x2sys_binlist, x2sys_cross, x2sys_datalist, x2sys_get, x2sys_init, x2sys_put, x2sys_report, x2sys_solve

       2015, P. Wessel, W. H. F. Smith, R. Scharroo, J. Luis, and F. Wobbe