There was a question asked previously here link(Drawing parallel lines inside polygons (Well Paths) using ArcGIS Desktop?), I was wondering if anyone has tried this in a more up to date ArcGIS Pro, I'm trying to replicate the solution to work out river widths.

# import libraries
import arcpy

# set input/output parameters
polyFC = arcpy.GetParameterAsText(0)        # input polygons
outParallel = arcpy.GetParameterAsText(1)   # output parallel lines
lineSpacing = arcpy.GetParameterAsText(2)   # line spacing
buffDist = arcpy.GetParameterAsText(3)      # inner buffer distance

# parse numbers from parameters
lineSpaceNum = float(lineSpacing.split(' ')[0])
buffNum = float(buffDist.split(' ')[0])

# establish spatial reference
desc = arcpy.Describe(polyFC)
SR = desc.spatialReference

# set overwrite environment
arcpy.env.overwriteOutput = True
arcpy.env.outputCoordinateSystem = SR

parallels = []
# loop through each input shape
for row in arcpy.da.SearchCursor(polyFC, ["SHAPE@"], spatial_reference=SR):

    # create inner buffer
    polyBuff = row[0].buffer(buffNum * -1)

    # create hull rectangle to establish a rotated area of interest
    coordSplit = row[0].hullRectangle.split(' ')

    # collect corner coordinates
    coordList = arcpy.Array([arcpy.Point(coordSplit[0],coordSplit[1]),arcpy.Point(coordSplit[2],coordSplit[3]),arcpy.Point(coordSplit[4],coordSplit[5]),arcpy.Point(coordSplit[6],coordSplit[7]),arcpy.Point(coordSplit[0],coordSplit[1])])

    # create lines from hull rectangle
    currentLines = []
    for pointNum in range(0,4):
        hullRecLine = arcpy.Polyline(arcpy.Array([coordList.getObject(pointNum),coordList.getObject(pointNum+1)]))

    # compare first and second line to determine if first line is short or long
    firstLong = 0
    if currentLines[0].length > currentLines[1].length:
        firstLong = 1

    # calculate number of points needed along short axis
    numPoints = int(math.floor(currentLines[firstLong].length/lineSpaceNum))

    # create and join points to create parallel lines
    for point in range(1,numPoints+1):
        shortPoint1 = currentLines[firstLong].positionAlongLine(lineSpaceNum*point)
        shortPoint2 = currentLines[firstLong + 2].positionAlongLine(currentLines[firstLong + 2].length - (lineSpaceNum*point))
        parallel = arcpy.Polyline(arcpy.Array([shortPoint1.centroid,shortPoint2.centroid]), SR)

        # intersect parallel lines with buffer
        parallelBuff = parallel.intersect(polyBuff,2)

# write geometries to disk
arcpy.CopyFeatures_management(parallels, outParallel)

# add to map
mxd = arcpy.mapping.MapDocument("CURRENT")
dataFrame = arcpy.mapping.ListDataFrames(mxd, "*")[0]
addLayer = arcpy.mapping.Layer(outParallel)
arcpy.mapping.AddLayer(dataFrame, addLayer)

del row
  • You've posted code, but not given any indication what it does or doesn't do. What is your question?
    – Vince
    Commented Aug 24, 2022 at 15:09
  • Sorry, I had included the original question in a link. gis.stackexchange.com/questions/114204/… Ideally I'd like to try the same solution to work the width of a cluster of river shapes (polygons). Thank you Commented Aug 24, 2022 at 16:58
  • GIS SE is a problem-solving site. All Questions should be able to answer the questions "What have you tried?" and "Where are you stuck?" You seem to be asking for others to try this for you instead.
    – Vince
    Commented Aug 24, 2022 at 18:44
  • What is the actual problem with the solution that you are trying? Commented Aug 26, 2022 at 0:24


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