Re: List Position
- To: mathgroup at smc.vnet.net
- Subject: [mg15784] Re: List Position
- From: "Allan Hayes" <hay at haystack.demon.co.uk>
- Date: Sun, 7 Feb 1999 02:04:00 -0500 (EST)
- References: <79eagc$9ig@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Harry flynn wrote in message <79eagc$9ig at smc.vnet.net>... >Can anyone tell me how I find the position in a list of the first value >less than or equal to zero. >For example, how can I get Mathematica to tell me that in the list >{{1},{1},{2},{8},{-3}} >that the first value of interest to me is position 5. Thanks in advance. >Harry. Position[ {{1},{1},{2},{8},{-3}}, {x_}/;x<=0, {1}, 1 ] {{5}} The HelpBrowser gives Position[expr, pattern, levspec, n] gives the positions of the first n parts of expr which match the pattern. Allan --------------------- Allan Hayes Mathematica Training and Consulting www.haystack.demon.co.uk hay at haystack.demon.co.uk Voice: +44 (0)116 271 4198 Fax: +44 (0)870 164 0565