```Date: Mon, 15 Aug 2005 13:16:08 -0400 Reply-To: Subject Coordinates Discussion List <[log in to unmask]> Sender: Subject Coordinates Discussion List <[log in to unmask]> From: "Colleen R. Cahill" <[log in to unmask]> Subject: Re: Question on form of coordinates (fwd) Comments: To: [log in to unmask] Content-Type: TEXT/PLAIN; charset=US-ASCII Forwarded by Moderator: As a Geographic Information Systems librarian and graduate of Geomatics, I am primarily concerned with coordinates which are easily extracted and mapped. If one were to create a GIS point or polygon feature class from MARC records, or use spatial coordinates to search MARC records, the easiest coordinates to use would be decimal degrees. However, I am sure you are aware that what you suggest in your message (N0421510) is not a decimal degree format. The decimal degree value for the coordinate you suggest would be 42.252778. Which is calculated from (15 minutes*60 seconds per minute)+10 seconds = 910 seconds. 910/3600 seconds per degree = 0.252778 + 42 degrees. In reverse, calculating the minutes and seconds from decimal degrees -- (42.252778 - 42)*3600 seconds per degree = 910.0008 seconds. 910.0008/60 seconds per minute = 15.16668 minutes. (15.16668 - 15 minutes)*60 seconds = 10.0008 or 10 seconds. Or similarly 0.252778 sec * 60 min/degree = 15.16668 min. And (15.16668 - 15 minutes)*60 seconds = 10.0008 or 10 seconds, which brings us back to 42/15/10. Instead of using N and E or S and W, the mapping presence is to have any proposed field use positive values to indicate coordinates in quadrants north of the Equator and east of Greenwich and negative values for south of the Equator and west of Greenwich. The other obstacle to a GIS/MARC interface has been the ability to search MARC coordinate fields using a patron specified integer coordinate values. Using a GIS interface it is possible to have patrons select a search area. It would be wonderful to be able to use the patron's selected coordinates to search MARC records. Currently, to the best of my knowledge, coordinate fields in MARC records are text based which prevent searches for ranges of integer values. I look forward to working on this with you and the group. Thanks Joe Joe Aufmuth GIS coordinator George A. Smathers Libraries Government Documents University of Florida P.O. Box 117001 Gainesville, Florida 32611-7001 352-273-0367 Fax: 352-392-3357 [log in to unmask] -----Original Message----- From: Subject Coordinates Discussion List [mailto:[log in to unmask]]On Behalf Of Colleen R. Cahill Sent: Monday, August 15, 2005 6:56 AM To: [log in to unmask] Subject: [SUBCOOR] Question on form of coordinates As a map cataloger, I primarily deal with coordinates in two forms: human-readable geographic coodinates (i.e. North 42 degrees, 15 minutes, 10 seconds) and machine-readable decimal degrees (i.e. N0421510). For the proposed subject coodinates, a machine-readable form of coordinates is needed and so I always think of decimal coordinates. This is form a standard used much? Are there any other (better or worse) ways used to present coordinates? Thank you! Colleen Colleen R. Cahill | [log in to unmask] Digital Production Coordinator | (202)707-8540 & Recommending Officer for | FAX (202)707-8531 Science Fiction & Fantasy | Library of Congress These opinions are mine, Mine, Mine! | Washington, DC 20540-4652 ``` Back to: Top of message | Previous page | Main SUBCOOR page
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