Fire up python and go all command line
>>> import math
>>> pnt_1 = [1.0,-1.0]
>>> pnt_0 = [0.0,0.0]
>>> radian = math.atan((pnt_1[0] - pnt_0[0])/(pnt_1[1] - pnt_0[1]))
>>> radian
-0.7853981633974483
>>> degrees = math.degrees(radian)
>>> if degrees < 0.0:
... degrees += 360
...
>>> degrees
315.0
>>>
If you want to determine the azimuth of a polyline, then you can use this field calculator function
''' input shape field: returns angle between 0 and <360 based upon the first and last point
polyline_azimuth(!Shape!) #enter into the expression box'''
import math
def polyline_azimuth(shape):
radian = math.atan((shape.lastPoint.X - shape.firstPoint.X)/(shape.lastPoint.Y - shape.firstPoint.Y))
degrees = math.degrees(radian)
if degrees <0:
return degrees + 360
else:
return degrees