Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site utah-gr.UUCP Path: utzoo!linus!philabs!pwa-b!utah-gr!thomas From: thomas@utah-gr.UUCP (Spencer W. Thomas) Newsgroups: net.med Subject: Re: The Perils of Nutrasweet: digits of precision Message-ID: <1542@utah-gr.UUCP> Date: Mon, 5-Aug-85 15:48:36 EDT Article-I.D.: utah-gr.1542 Posted: Mon Aug 5 15:48:36 1985 Date-Received: Sun, 11-Aug-85 03:46:10 EDT References: <771@burl.UUCP> <394@petrus.UUCP> <182@steinmetz.UUCP> Reply-To: thomas@utah-gr.UUCP (Spencer W. Thomas) Organization: Univ of Utah CS Dept Lines: 20 Summary: In article <622@ttidcc.UUCP> hollombe@ttidcc.UUCP (The Polymath) writes: >I agree. 10% has only one significant digit, but .007% has three. The >decimal point makes the two leading zeros significant (i.e.: the original >article claims accuracy to three decimal places). > The original article may claim accurace to 3 decimal places, but the way I learned significant digits, you should write 0.00700% to specify 3 digits of accuracy. 10% is a toughie - you really can't tell whether the meaning is 10%+/-5% (1 digit) or 10%+/-.5% (2 digits). For 3 digits, you should write 10.0%. The best way to write numbers to clearly specify the number of siginificant digits is to use scientific notation. Thus: 1 digit 3 digits 7e-3 7.00e-3 1e+1 1.00e+1 -- =Spencer ({ihnp4,decvax}!utah-cs!thomas, thomas@utah-cs.ARPA) "You don't get to choose how you're going to die. Or when. You can only decide how you're going to live." Joan Baez