Calculating distance between two GPS locations based on Location's date?

Question

I'm using ArcMap 10.2.1. I have GPS collar data from which I'm trying to determine the farthest distance moved by an individual each day. Therefore, I need to take the first point recorded in a day and measure it to each location recorded that day. I've investigated using Near and Point Distance, however, these methods either compare all combinations of points or the ones in a self-provided buffer. Any ideas or thoughts?

Answer 1

Assuming first point is record that appears first for given date set.

WORKFLOW:

# find coordinates of first point
arcpy.AddField_management("random", "dateText", field_type="TEXT")
arcpy.CalculateField_management("random", "dateText", """!Date!.split(" ")[0]""", expression_type="PYTHON_9.3")
arcpy.AddGeometryAttributes_management("random", "POINT_X_Y_Z_M")
arcpy.Statistics_analysis("random", "D:/Scratch/first.dbf", "POINT_X FIRST;POINT_Y FIRST", case_field="dateText")
# find distances
arcpy.AddField_management("random", "DISTANCE", "DOUBLE")
arcpy.AddJoin_management("random", "dateText", "first", "dateText", "KEEP_ALL")
arcpy.CalculateField_management("random", "random.DISTANCE", "math.hypot( !random.POINT_X! - !first.FIRST_POIN!, !random.POINT_Y!- !first.FIRST_PO_1!)", expression_type="PYTHON_9.3")
arcpy.RemoveJoin_management(in_layer_or_view="random", join_name="")
# summarise by date
arcpy.Statistics_analysis("random", "D:/Scratch/results.dbf", "DISTANCE MAX", case_field="dateText")

Perhaps modify "dateText" in above by concatenation with individual ID

Answer 2

It sounds like you are saying that to determine point distances between all points in your feature class will be too much processing when you only need to do it for the points captured on a single day.

Consequently, I think you should use the Select (Analysis) tool to select out points for that day into a separate (temporary) feature class and just run Point Distance on that.

This will cut the number of permutations that need to be calculated dramatically.