create points and lines both from excel
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09-27-2016 05:53 PM
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Thanks Xander,
Let's say we have oly 5 points created by the tool "create random points". Also, assume we have the lines:
| 1 | 2 |
| 1 | 5 |
| 2 | 5 |
| 3 | 4 |
| 3 | 1 |
| 4 | 5 |
| 4 | 2 |
| 4 | 3 |
To create the lines, use the tool "xy to lines" and this is what we get:
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XanderBakker
OK, so I created a script that is capable of creating the 300 random points and connect them to 409 lines without intersections of lines. See below the result of two separate runs:
and
Note that there can be points that do not participate in any line.
The script that created these results is listed below:
import arcpy
def main():
import random
import math
arcpy.env.overwriteOutput = True
# featureclasses and sr
fc_pnt = r'C:\GeoNet\RandomPoints2Lines\data.gdb\points'
fc_line = r'C:\GeoNet\RandomPoints2Lines\data.gdb\lines'
sr = arcpy.SpatialReference(3116)
# 409 lines from 300 points
number_lines = 409
number_points = 300
max_diag_cutoff = 0.2 # use 20% of diagonal of extent for max distance between points
min_diag_cutoff = 0.05 # use a minimum dist too
# extent for generating the random points
xmin = 830000
xmax = 838000
ymin = 1180000
ymax = 1186000
# create the random points
print "create the random points"
points = []
dct_pntg = {}
for oid in range(number_points):
x = random.randrange(xmin, xmax)
y = random.randrange(ymin, ymax)
pnt = arcpy.Point(x, y)
pntg = arcpy.PointGeometry(pnt, sr)
points.append(pntg)
dct_pntg[oid] = pntg
# store the random points
arcpy.CopyFeatures_management(points, fc_pnt)
# get diagonal length of extent
diag_length = math.hypot(xmax-xmin, ymax-ymin)
max_dist_allowed = diag_length * max_diag_cutoff
min_dist_allowed = diag_length * min_diag_cutoff # can be set to 0
# create a dct of distances
print "create a dct of distances"
dct_dist = {}
cnt = 0
for oid1, pntg1 in sorted(dct_pntg.items()):
if oid1 % 25 == 0:
print "oid1", oid1
for oid2 in range(oid1, number_points):
cnt += 1
pntg2 = dct_pntg[oid2]
dist = getDistance(pntg1, pntg2)
if all([dist <= max_dist_allowed, dist >= min_dist_allowed]):
oid_key = "{0}#{1}".format(oid1, oid2)
dct_dist[oid_key] = dist
print "number of possible lines:", cnt
print "lines to be considered:", len(dct_dist.keys())
# let's create some lines
print "let's create some lines"
dct_lines = {}
for oid_key, dist in dct_dist.items():
lst_oid = oid_key.split('#')
oid1 = int(lst_oid[0])
oid2 = int(lst_oid[1])
polyline = createLine(dct_pntg[oid1], dct_pntg[oid2])
if linesIntersect(dct_lines, polyline, oid_key) == False:
dct_lines[oid_key] = polyline
if len(dct_lines.keys()) >= number_lines:
break
# store the result:
print "store the result"
lines_found = dct_lines.values()
arcpy.CopyFeatures_management(lines_found, fc_line)
def getDistance(pntg1, pntg2):
'''Calculate the distance between two point geometries'''
return pntg1.distanceTo(pntg2)
def createLine(pntg1, pntg2):
'''Create a line from two point geometries'''
sr = pntg1.spatialReference
return arcpy.Polyline(arcpy.Array([pntg1.firstPoint, pntg2.firstPoint]), sr)
def linesIntersect(dct_lines, polyline, oid_key):
'''Verify if lines cross (lines may share start and end points)'''
intersect = False
lst_oid = oid_key.split('#')
oid1 = int(lst_oid[0])
oid2 = int(lst_oid[1])
for oid_key2, line in dct_lines.items():
lst_oid2 = oid_key2.split('#')
oid3 = int(lst_oid2[0])
oid4 = int(lst_oid2[1])
if all([oid3 != oid1, oid3 != oid2, oid4 != oid1, oid4 != oid2]):
if line.crosses(polyline):
intersect = True
break
return intersect
if __name__ == '__main__':
main()To run this script you will have to change a number of settings according to your specific needs:
- lines 10 and 11 the output featureclass that will be created for the random points and lines
- line 12 the spatial reference to be used for the output featureclasses
- lines 15 and 16 set the number of points and lines to be created
- lines 17 and 18 set the minimum and maximum lengths of the lines to be created (possibilities to be considered). Long lines are more probable to have intersections so don't make them too long and perhaps it is not desired that points located directly next to each other are considered in the process
- lines 21 to 24 indicate the extent in which the random points will be created
Try it for yourself and see what the result is. If you have any problems please let me know and we'll see how we can fix it.
Kind regards, Xander
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