Report statistics from crossover data base
Note: No space is allowed between the option flag and the associated arguments.
x2sys_report will read the input crossover ASCII data base coedbase.txt (or stdin) and report on the statistics of crossovers (n, mean, stdev, rms, weight) for each track. Options are available to let you exclude tracks and limit the output.
- The name of the input ASCII crossover error data base as produced by x2sys_cross. If not given we read standard input instead.
- Specify which data column you want to process. Crossovers related to this column name must be present in the crossover data base.
- Specify the x2sys TAG which identifies the attributes of this data type.
- Eliminate COEs by distributing the COE between the two tracks in proportion to track weight and producing (dist, adjustment) spline knots files for each track (for the selected column). Such adjustments may be used by x2sys_datalist. The adjustment files are called track.column.adj and are placed in the $X2SYS_HOME/TAG directory. For background information on how these adjustments are designed, see Mittal .
- Name of ASCII file with a list of track names (one per record) that should be excluded from consideration [Default includes all tracks].
- 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.
- Only report data from tracks involved in at least nx_min crossovers [all tracks].
- Append e for external crossovers or i for internal crossovers only [Default is external].
- 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). Set geographic regions by specifying ISO country codes from the Digital Chart of the World using -Rcode1,code2,…[+r|R[incs]] instead: Append one or more comma-separated countries using the 2-character ISO 3166-1 alpha-2 convention. To select a state of a country (if available), append .state, e.g, US.TX for Texas. To specify a whole continent, prepend = to any of the continent codes AF (Africa), AN (Antarctica), AS (Asia), EU (Europe), OC (Oceania), NA (North America), or SA (South America). Use +r to modify the bounding box coordinates from the polygon(s): Append inc, xinc/yinc, or winc/einc/sinc/ninc to adjust the region to be a multiple of these steps [no adjustment]. Alternatively, use +R to extend the region outward by adding these increments instead, or +e which is like +r but it ensures that the bounding box extends by at least 0.25 times the increment [no extension]. 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 and registration, if applicable) are copied from the grid. Appending +uunit 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.
- 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].
- -^ or just -
- Print a short message about the syntax of the command, then exit (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 exit.
- -? or no arguments
- Print a complete usage (help) message, including the explanation of all options, then exit.
- Temporarily override a GMT default setting; repeatable. See gmt.conf for parameters.
To report statistics of all the external magnetic crossovers associated with the tag MGD77 from the file COE_data.txt, restricted to occupy a certain region in the south Pacific, try
gmt x2sys_report COE_data.txt -V -TMGD77 -R180/240/-60/-30 -Cmag > mag_report.txt
To report on the faa crossovers globally that involves track 12345678, try
gmt x2sys_report COE_data.txt -V -TMGD77 -Cfaa -S2345678 > faa_report.txt
Mittal, P. K. (1984), Algorithm for error adjustment of potential field data along a survey network, Geophysics, 49(4), 467-469.