2001-10-25  Andreas J. Guelzow <aguelzow@taliesin.ca>

	* src/analysis-tools.c : various routines added to keep track of missing
	  observations as well as various routines removed that are no longer
	  required. Renamed data_set_t to old_data_set_t, and introduced a new
          data_set_t
	(correlation_tool) : now handles missing observations and permits disconnected
          rectangular data regions
	(covariance_tool) : ditto
	(descriptive_stat_tool) : now permits disconnected rectangular data regions
	(sampling_tool) : now permits samples of multiple datasets as well as multiple
	  samples.
	* src/analysis-tools.h : new group_by_t type
	* src/ranges.c (global_range_parse) : fix bug (relative references were
          evaluated with respect to B2 rather than A1)

2001-10-25  Andreas J. Guelzow <aguelzow@taliesin.ca>

	* correlation.glade : add `group by area' radio button
	* covariance.glade : ditto
	* descriptive-stats.glade: ditto
	* sampling.glade : added group_by buttons as well as multiple sample entry
	* dialog-analysis-tools.c (parse_output) : initialize all fields of dao
	(dialog_tool_init) : add argument specifying the flags for the input
          expression entry widgets
	(tool_update_sensitivity_multiple_areas_cb) : new routine,
          tool_update_sensitivity_cb for multiple input ranges
	(corr_tool_ok_clicked_cb) : use global_range_list_parse rather than parse_range,
          call tool with modified argument list
	(cov_tool_ok_clicked_cb) : ditto
	(desc_stats_tool_ok_clicked_cb) : ditto
	(sampling_tool_ok_clicked_cb) : ditto, as well as support for group_by and multiple
          samples
	* tools.h : changed arguments for correlation_tool, covariance_tool,
          descriptive_stat_tool, and sampling_tool