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