I’ve been trying for days to get the start and endpoint from a line/curve in Python so that I can work with it. Now I suspect it has something to do with the installation of Dynamo, Python, or a problem with clr.AddReference('ProtoGeometry'). How can I test it, or does someone have a better suggestion? Thanks and best regards, Igor.
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@ib9YMLD ,
the key is you need geometry…
import sys
import clr
clr.AddReference("RevitAPI")
from Autodesk.Revit.DB import *
clr.AddReference("RevitNodes")
import Revit
clr.ImportExtensions(Revit.GeometryConversion)
clr.AddReference("RevitServices")
import RevitServices
from RevitServices.Persistence import DocumentManager
from RevitServices.Transactions import TransactionManager
clr.AddReference("ProtoGeometry")
from Autodesk.DesignScript import *
doc = DocumentManager.Instance.CurrentDBDocument
uidoc = DocumentManager.Instance.CurrentUIApplication.ActiveUIDocument
# 🛒🛒 collect
detailLines = FilteredElementCollector(doc).OfCategory(BuiltInCategory.OST_Lines).WhereElementIsNotElementType().ToElements()
# 🎲 geometry
_lines = [ i.Location.Curve.ToProtoType() for i in detailLines]
# 🔴🟠🟡points
startPoints = [i.StartPoint for i in _lines]
endPoints = [i.EndPoint for i in _lines]
OUT = startPoints, endPoints
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Hi,
I could be wrong, but I think it has something to do with a wrong ChatGPT response. 
5 Likes
Hi
# Load the Python Standard and DesignScript Libraries
import sys
import clr
clr.AddReference('ProtoGeometry')
from Autodesk.DesignScript.Geometry import *
#Input variable of "Lines"
lines = IN[0]
#First we check if the item coming in is not already a list. We make it one if it is not.
if not isinstance(lines, list):
lines = [lines]
#Creating an empty container to put our results in
results = []
#Here we check each element (Line) inside the list (Lines)
for line in lines:
#If there is one element, we treat it a different way to multiple
if len(lines) > 1:
#We append the results to our empty "results" container
results.append([line.StartPoint, line.EndPoint])
else:
#We append the results to our empty "results" container
results.append(line.StartPoint)
results.append(line.EndPoint)
#We return our "results" container out of the Python node back to Dynamo
OUT = results
edit:How Can I get start and end point using python - #3 by solamour
cordially
christian.stan
3 Likes
I gave up on ChatGPT 
from code of M. Draxl
clr.AddReference("RevitNodes")
import Revit
clr.ImportExtensions(Revit.GeometryConversion)
#Input variable of "Lines"
lines = UnwrapElement(IN[0]).Location.Curve.ToProtoType()
1 Like
ChatGpt had a sharp nose, he took a code from Mr. Sol Amour
3 Likes
Excuse me, I made a mistake in case of List
here is correction
# Load the Python Standard and DesignScript Libraries
import sys
import clr
clr.AddReference('ProtoGeometry')
from Autodesk.DesignScript.Geometry import *
clr.AddReference("RevitNodes")
import Revit
clr.ImportExtensions(Revit.GeometryConversion)
#Input of "elt"
elt = UnwrapElement(IN[0])
#First we check if the item coming in is not already a list. We make it one if it is not.
if not isinstance(elt, list):
elt = [elt]
#Creating an empty container to put our results in
results = []
#Here we check each element (Line) inside the list (Lines)
for e in elt:
#If there is one element, we treat it a different way to multiple
if len(elt) > 1:
#We append the results to our empty "results" container
results.append([e.Location.Curve.ToProtoType().StartPoint, e.Location.Curve.ToProtoType().EndPoint])
else:
#We append the results to our empty "results" container
results.append(e.Location.Curve.ToProtoType().StartPoint)
results.append(e.Location.Curve.ToProtoType().EndPoint)
#We return our "results" container out of the Python node back to Dynamo
OUT = results
Sincerely
christian.stan
1 Like
Thanks, Christian, Stan, and Draxl-Andreas,
The solution from Stan is working for me. I have to admit that the one from Draxl-Andreas is providing too many start and end points for one line; I have to spend time understanding why.
It’s everything under clr. until the input line that is killing me with Python. Best Regards, Igor.
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Mr. Draxl’s code collects all the Detail lines of your project
that’s why you have a lot of points
Sincerely
christian.stan
1 Like
Darn ! , I’ve been fooled, they have pretty much the same writing syntax for comments 
2 Likes