.-
help for ^mfilegr^
.-

View and save multiple graphs with filenames based on a numeric identifier
--------------------------------------------------------------------------

 ^mfilegr^  y-variable x-variable, ^id^var^(^string^)^  ^unit(^string^)^
                                 [^view^|^noview^  graph_options]

Description
-----------

This program constructs one two-way plot of y-var against x-var for each
value of a grouping (id) variable.  Each graph is saved to a file whose
name is the respective value of the id variable.

Options
-------

^id^var(string) where "string" is the name of an existing variable in the
 data that is the identifier for each group of values, y-var and x-var,
 for which a graph is desired.  This id variable must be numeric.
 It is NOT optional.

^view^|^noview^ is a switch that controls display of graphs.  If ^view^
 is specified each graph is displayed to screen as it is saved to disk and
 a ^more^ condition is set such that the user must press a key to process
 the next graph. The  default is ^noview^, so that graphs are not displayed
 but just saved to disk.

^unit^(string) specifies the string used to form the ^b1^(title) of the
  graphs. For example, if ^unit(^farm^)^ is specified, then the graphs
  will be entitled farm #240  farm #3567 etc, depending on the values
  of the id variable specified by ^id^var(). This is NOT optional.

graph_options are any of the graph options for a two-way graphic EXCEPT:
  (1) the ^saving()^ option, because the latter is built into the ^mfilegr^
      command in a special way.  
  (2) the ^b1(^"title"^)^ option because this is set within the program
      to label the graphs, depending on the argument of the ^unit^ 
      option.
   
   There are no error traps to prevent you from specifying these options, 
   just don't do it.

   Of course many options will not make sense from one graph to another,
   for example, specifying values for ^ylab^(..) and ^xlab^(..) may not carry
   over sensibly.  But a simple ^ylab^ ^xlab^, allowing Stata to choose
   reasonable values for each graph, may be sensible.


Example
-------

. ^describe^

Contains data from dohoo.dta
  obs:            11                          
 vars:             3                          20 Jul 1999 20:27
 size:           144 (100.0% of memory free)
------------------------------------------------------------------------
   1. id        float  %9.0g                  farm identifier
   2. xvar      float  %9.0g                  rainfall
   3. yvar      float  %9.0g                  crop yield
------------------------------------------------------------------------
Sorted by:  

. ^list^

            id       xvar       yvar 
  1.        12          4          9  
  2.        12          5          7  
  3.        12          1          2  
  4.        13          4          8  
  5.        13          6          5  
  6.        13          1          9  
  7.        23          1          8  
  8.        23          7          8  
  9.        23          4          9  
 10.      4890          7          1  
 11.      4890         12          3  


. ^mfilegr^ yvar xvar, idvar(id) unit(farm) noview xlab ylab

 **** no display ****

. ^dir^ *.gph
   0.3k   7/20/99 23:44  12.gph            
   0.3k   7/20/99 23:44  13.gph            
   0.3k   7/20/99 23:44  23.gph            
   0.3k   7/20/99 23:44  4890.gph          

  


Author
------

Dr Philip Ryan
Department of Public Health
University of Adelaide
pryan@@medicine.adelaide.edu.au

