hoe bereken je de cumulatieve afstand tussen punten?

Question

<\/HEAD>hallo mensen, ik probeer de cumulatieve afstand te berekenen voor een reeks punten die zich in een lineair patroon bevinden. Ik gebruik ArcGIS 10.3.1 Standard licence.<\/P><\/BODY><\/HTML>

DanPatterson_Retired · Answer

""" input shape field: returns cumulative distance between points dist_cumu(!Shape!) 
#enter into the expression box"""
x0 = 0.0;  y0 = 0.0;  distance = 0.0
def dist_cumu(shape):
      global x0;  global y0;  global distance
      x = shape.firstpoint.X;  y = shape.firstpoint.Y
      if x0 == 0.0 and y0 == 0.0:
          x0 = x; y0 = y
      distance += math.sqrt((x - x0)**2 + (y - y0)**2)
      x0 = x;  y0 = y
      return distance

DanPatterson_Retired · Answer

If you want distance from the first point in a data table to every other point in sequence,  then use cumulative distance function below.

Do the following:

* select Python parser
* toogle on Show  code block
* paste the following in the Pre-logic Script Code block
* and the last piece in the expression box

Pre-logic Script Code:

""" input shape field: returns cumulative distance between pointsdist_cumu(!Shape!)    #enter into the expression box"""  x0 = 0.0;  y0 = 0.0;  distance = 0.0  def dist_cumu(shape):      global x0;  global y0;  global distance      x = shape.firstpoint.X;  y = shape.firstpoint.Y      if x0 == 0.0 and y0 == 0.0:          x0 = x; y0 = y      distance += math.sqrt((x - x0)**2 + (y - y0)**2)      x0 = x;  y0 = y      return distance

should do it... syntax highlighting isn't taking this morning