Click here to see the SAS code.
Click here to see the example.

-------------------------------------------------

See my blog for more information about this graph!


This is my SAS/Graph imitation of:
http://www-bcs.mit.edu/gaz/demos/koffka.html


This is another purely-annotate example.

The text was the easy part - I just started each piece at the same
x-coordinate, so it would look left-justified.

Then for the koffka rings graphics, I did them 1/2 at a time.
For each half, I did a rectangle, then a large 1/2-circle (pie),
and then a small 1/2-circle.  When the 2 halfs are touching 
(like in the first picture) it looks like the large circle is
continuous (but it's really 2 pieces).

By having it in 2 pieces, that makes it an easy matter to 
separate the 2 halves in the 2nd picture, and to skew the 
2 halves up/down in the 3rd picture.

To help "prove" that the illusion is an illusion, I have used
the annotate data set's html variable to encode html title= 
charttips/flyover-text, so you can hover your mouse over the
various pieces of the graphic, and see the RGB hex color value
of that piece (this way you can see the hex values of colors
that your eye thinks are different, and prove to yourself 
that they are actually the same - koffka illusion, with proof!)

The koffka rings is a really neat "illusion", and it's even 
"neater" that this graphic can be done in sas :)

Back to Samples Index