Date: Tue, 26 Jan 1999 08:20:25 -0500
Reply-To: "Hudson, Spencer" <shudson@VIROPHARMA.COM>
Sender: "SAS(r) Discussion" <SAS-L@UGA.CC.UGA.EDU>
From: "Hudson, Spencer" <shudson@VIROPHARMA.COM>
Subject: SAS Q: Automatic aesthetic major tick marks on gplot axes
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Given a range of data, is there an easy way of automatically determining
a set of aesthetically pleasing values at which to draw and label major
tick marks on a gplot. For example, a panel of clinical laboratory tests
may include serum cholesterol with a range of 73 to 352 for which a
'nice' set might be 70 to 360 by 30. The range of values of serum
potassium has a range of 2.4 to 11.6, for which a 'nice' set might be 2
to 12 by 2. Can this choice of values be automated? If so, how? Possibly
a more interesting and difficult question would be: How do we define
'nice'? I have looked in both of Cleveland's book and Tufte's first book
and could not find much guidance, other than the usual advice of not
using too many ticks and use rounded values.
Any ideas will be appreciated.
Spencer Hudson, Ph.D.
Director, Biostatistics and Clinical Data Management
405 Eagleview Blvd
Exton, PA 19341
Telephone: (610) 458-7300 ext. 154
FAX: (610) 458-7380
Ticker: VPHM on NASDAQ
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