./display_system.pl [ options ] <systemname> <code> [args...]


Displays the signals generated for the system <systemname> for market <code> over the selected interval. A system is comprised of a long and a short signal which are each displayed when they trigger (printing 'long' and 'short', respectively).


--full, --start=<date>, --end=<date>, --nb-item=<nr>

Determines the time interval to consider for analysis. In detail:

--start=2001-1-10, --end=2002-11-17

The start and end dates considered for analysis. The date needs to be in the format configured in ~/.gt/options and must match the timeframe selected.


The number of periods to use in the analysis.


Consider all available periods.

The periods considered are relative to the selected time frame (i.e., if timeframe is "day", these indicate a date; if timeframe is "week", these indicate a week; etc.). In GT format, use "YYYY-MM-DD" or "YYYY-MM-DD hh:mm:ss" for days (the latter giving intraday data), "YYYY-WW" for weeks, "YYYY/MM" for months, and "YYYY" for years.

The interval of periods examined is determined as follows:

  1. if present, use --start and --end (otherwise default to last price)
  2. use --nb-item (from first or last, whichever has been determined), if present
  3. if --full is present, use first or last price, whichever has not yet been determined
  4. otherwise, consider a two year interval.

The first period determined following this procedure is chosen. If additional options are given, these are ignored (e.g., if --start, --end, --full are given, --full is ignored).


The timeframe can be any of the available modules in GT/DateTime.


Display results for the last period only. Overrides any other options given to determine the interval.


Determines the number of periods (back from the last period) that are loaded for a given market from the data base. Care should be taken to ensure that these are consistent with the performed analysis. If not enough data is loaded to satisfy dependencies, for example, correct results cannot be obtained. This option is effective only for certain data base modules and ignored otherwise.


A configuration option (typically given in the options file) in the form of a key=value pair. For example, --option=DB::Text::format=0 sets the format used to parse markets via the DB::Text module to 0.



The name of the system you want to test. This can be any module under GT/Systems.


The symbol for which you wish to display the signal. Use whatever symbols are available in your database.


Args are passed to the new call that will create the system. args is a string that specifies the signal in gt terms, spaces and other chars that the shell interprets will need to be quoted in some way.


  ./display_system.pl SY:G IBM {S:G:CrossOverUp {I:Prices CLOSE} {I:EMA}} {S:G:CrossOverDown {I:Prices CLOSE} {I:EMA}}

A long signal is generated when Prices cross up over the EMA, while a short signal is generated when Prices cross down over the EMA.