Add dashed lines to graphs --------------------------
^dashln^ y0 x0 y1 x1, [, ^DA^sh(dashlength) ^SP^ace(spacelength) ^P^en(pen#) ^B^egin ^M^ore ^DR^aw ^SAV^ing^(^fname^)^]
^dashln^ adds one or more specified dashed straight lines to a Stata graph just drawn. The lines extend from y0,x0 to y1,x1 where values are given in the scale of the data. The line style can be adjusted by specifying the length of the dashes and relative amount of space between dashes as well as the pen #.
Options ------- ^dash^, ^space^, and ^pen^ values may be specified to adjust the line style. The value for ^dash^ indicates the length of each dash in virtual pixels, default=200. The ^space^ value indicates the amount of blank space between dashes, as a percent of dash size, default=150. The ^pen^ number indicates which graph pen to use, default=2.
^Begin^ should be specified for the first line if several lines are desired on the graph. Global macros are used to store multiple line info and the use of ^begin^ clears these macros and starts recording new line info.
^More^ should be specified after the first line (begin) and before the last line of a multi-line graph, informing ^dashln^ that the graph should not yet be drawn. If you want to see the graph updated after each line is specified, then use ^draw^ instead of ^more^.
^Draw^ should be specified with multi-line graphs when you want the graph drawn. You can specify ^draw^ multiple times and see how the graph progresses, it doesn't prevent further additions using ^more^ or ^draw^.
^Saving(^filename^)^ saves the resulting graph in filename.gph. In multi-line graphs, saving must be combined with ^draw^. The user is responsible for ensuring that the filename is valid and not already existing.
The command must be issued after a graph command and is intended for use with scatterplots. The user can attempt to draw lines on other types of plots (e.g., bar graphs), but the results can be unpredictable due to Stata's treatment x axis scaling and the results returned by the graph command.
The line drawn by ^dashln^ will extend beyond the data region of the graph if values outside the scales are specified.
. ^graph length weight, yla xla^ . ^dashln 155 2000 240 4900^ . ^dashln 155 2000 240 4900, dash(1000) space(50)^ a multi-line graph . ^dashln 155 2000 240 4900, begin^ . ^dashln 230 2000 160 4900, more^ . ^dashln 175 2500 225 4100, dash(400) space(200) pen(9) draw saving(te > st1)^
Author ------ Michael Blasnik, Blasnik & Associates, Boston, MA mblasnik@@110.net
Also see --------
On-line: ^help^ for @gph@