.. index:: ! x2sys_datalist .. include:: ../module_supplements_purpose.rst_ **************** x2sys_datalist **************** |x2sys_datalist_purpose| Synopsis -------- .. include:: ../../common_SYN_OPTs.rst_ **gmt x2sys_datalist** *track(s)* **-T**\ *TAG* [ |-A| ] [ |-E| ] [ |-F|\ *name1*,\ *name2*,... ] [ |-I|\ [*list*] ] [ |-L|\ [*corrections*] ] [ |SYN_OPT-R| ] [ |-S| ] [ [ |SYN_OPT-V| ] [ |SYN_OPT-bo| ] [ |SYN_OPT-do| ] [ |SYN_OPT-h| ] [ |SYN_OPT--| ] |No-spaces| Description ----------- **x2sys_datalist** reads one or more files and produces a single ASCII [or binary] table. The files can be of any format; this information is encoded in the TAG set with the |-T| option. You may limit the output to a geographic region, and insist that the output from several files be separated by a multiple segment header. Only the named data fields will be output [Default selects all columns]. Required Arguments ------------------ .. include:: explain_track.rst_ .. include:: explain_tag.rst_ Optional Arguments ------------------ .. _-A: **-A** Eliminate COEs by distributing the COE between the two tracks in proportion to track weight. These (dist, adjustment) spline knots files for each track and data column are called *track.column*.adj and are expected to be in the **$X2SYS_HOME**/*TAG* directory. The adjustments are only applied if the corresponding adjust file can be found [No residual adjustments]. .. _-E: **-E** Enhance ASCII output by writing GMT segment headers between data from each track [no segment headers]. .. _-F: **-F**\ *name1*,\ *name2*,... Give a comma-separated sub-set list of column names defined in the format definition file. [Default selects all data columns]. .. _-I: **-I**\ [*list*] Name of ASCII file with a list of track names (one per record) that should be excluded from consideration [Default includes all tracks]. .. _-L: **-L**\ [*corrections*] Apply optimal corrections to columns where such corrections are available. Append the correction table to use [Default uses the correction table *TAG*\ \_corrections.txt which is expected to reside in the **$X2SYS_HOME**/*TAG* directory]. For the format of this file, see CORRECTIONS below. .. _-R: .. |Add_-Rgeo| replace:: For Cartesian data just give *xmin/xmax/ymin/ymax*. This option limits the COEs to those that fall inside the specified domain. .. include:: ../../explain_-Rgeo.rst_ .. _-S: **-S** Suppress output records where all the data columns are NaN [Default will output all records]. .. |Add_-V| replace:: |Add_-V_links| .. include:: /explain_-V.rst_ :start-after: **Syntax** :end-before: **Description** .. |Add_-bo| unicode:: 0x20 .. just an invisible code .. include:: ../../explain_-bo.rst_ .. |Add_-do| unicode:: 0x20 .. just an invisible code .. include:: ../../explain_-do.rst_ .. |Add_-h| unicode:: 0x20 .. just an invisible code .. include:: ../../explain_-h.rst_ .. include:: ../../explain_help.rst_ Examples -------- To extract all data from the old-style MGG supplement file c2104.gmt, recognized by the tag GMT: :: gmt x2sys_datalist c2104.gmt -TGMT > myfile To make (*lon, lat*), and *depth* input for :doc:`blockmean ` and :doc:`surface ` using all the files listed in the file tracks.lis and defined by the tag TRK, but only the data that are inside the specified area, and make output binary, run:: gmt x2sys_datalist =tracks.lis -TTRK -Flon,lat,depth -R40/-30/25/35 -bo > alltopo_bin.xyz Corrections ----------- The correction table is an ASCII file with coefficients and parameters needed to carry out corrections. This table is usually produced by **x2sys_solve**. Comment records beginning with # are allowed. All correction records are of the form *trackID observation correction* where *trackID* is the track name, *observation* is one of the abbreviations for an observed field contained in files under this TAG, and *correction* consists of one or more white-space-separated *term*\ s that will be **subtracted** from the observation before output. Each *term* must have this exact syntax: *factor*\ [\*[*function*]([*scale*](\ *abbrev*\ [-*origin*]))[^\ *power*]] where terms in brackets are optional (the brackets themselves are not used but regular parentheses must be used exactly as indicated). No spaces are allowed except between *term*\ s. The *factor* is the amplitude of the basis function, while the optional *function* can be one of sin, cos, or exp. The optional *scale* and *origin* can be used to translate the argument (before giving it to the optional function). The argument *abbrev* is one of the abbreviations for columns known to this TAG. However, it can also be one of the three auxiliary terms **dist** (for along-track distances), **azim** for along-track azimuths, and **vel** (for along-track speed); these are all sensitive to the **-C** and |-N| settings used when defining the TAG; furthermore, **vel** requires **time** to be present in the data. If *origin* is given as **T** it means that we should replace it with the value of *abbrev* for the very first record in the file (this is usually only done for *time*). If the first data record entry is NaN we revert *origin* to zero. Optionally, raise the entire expression to the given *power*, before multiplying by *factor*. The following is an example of fictitious corrections to the track ABC, implying the **z** column should have a linear trend removed, the field **obs** should be corrected by a strange dependency on latitude, **weight** needs to have 1 added (hence correction is given as -1), and **fuel** should be reduced by a linear distance term: ABC z 7.1 1e-4\*((time-T)) ABC obs 0.5\*exp(-1e-3(lat))^1.5 ABC weight -1 ABC fuel 0.02\*((dist)) .. include:: x2sys_refs.rst_ See Also -------- :doc:`blockmean `, :doc:`gmt `, :doc:`surface `, :doc:`x2sys_init`, :doc:`x2sys_datalist`, :doc:`x2sys_get`, :doc:`x2sys_list`, :doc:`x2sys_put`, :doc:`x2sys_report`, :doc:`x2sys_solve`