%grloga
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Description
  The %grloga macro will create a gif file showing an animated
  graph of a logistic regression curve varying the intercept 
  (value of a) or varying the slope (value of b) and save it 
  as a gif file.  The gif file could be used as a graph 
  in a web page.

Syntax
  %gifinit(fname=);
  %grloga(a=,vary=b);
or
  %grloga(b=,vary=a);

Examples
  To make a graph varying b with a held constant at .3,
  and saving the gif file as c:\teaching\log4.gif
  with width of 300 pixels and height of 200 pixels, 
  you would type.

  %gifinit(fname=c:\teaching\log4.gif,h=300,v=200);
  %grloga(a=.3,vary=b);

  To save the file as c:\teaching\log5.gif with the
  same size, but varying b from -2 to 2 in increments
  of 0.05 with a delay of 10 milliseconds between 
  frames, you would type.

  %gifinit(fname=c:\teaching\log5.gif,h=300,v=200);
  goptions delay=10;
  %grloga(a=.3,vary=b,hi=2,lo=-2,inc=0.05);


Author
  Michael Mitchell
  mnm@ucla.edu
  UCLA Academic Technology Services
  Statistical Consulting Group

Also See

  See a complete example in
    http://www.ats.ucla.edu/stat/sas/teach/grlog/grlog.htm
    
  Also see the macro itself from
    http://www.ats.ucla.edu/stat/sas/macros/grloga.sas.txt