How can I calculate the min of other fields. For example I have 3 field: a, b and c. I want to have a filed that show me the minimum value of the 3 field. Finally I want to know the minimum value is of a or b or c. Thank you.
Using Python in the Field Calculator, here's how you would determine the minimum value across 3 fields.
Then to identify which of the 3 fields contains the minimum value, you can just do a series of Select By Attributes queries
"field1" = "minfield" (or whatever you call your new minimum value field)
then calculate a new text field equal to whichever field name you use in your query.
Here are code snippets for ArcGIS 10.0