Determining if polyline has true curve using ArcPy with ArcMap

Question

I'm using ArcPy with ArcMap 10.7.1.

I want to densify SDE.ST_GEOMETRY polylines if (and only if) the polylines have true curves.

If I were using ArcPy with the latest version of ArcGIS Pro (instead of ArcMap), then I think the hasCurves property could be used:

for row in cursor:
    polyline = row[0]
    if polyline.hasCurves() == True:
        polyline = polyline.densify('ANGLE', 10, 0.174533) #radians

Unfortunately, the hasCurves property doesn't seem to be available for a Polyline in ArcMap 10.7.1.

#ArcPy/ArcMap 10.7.1

AttributeError: 'Polyline' object has no attribute 'hasCurves'              

In ArcMap 10.7.1, is there an alternative option for determining if polylines have true curves?

Answer 1

I can't make any guarantees about preserving topology, but I will say that I've used the WKT trick before with success. IIRC, it looked something like this:

with arcpy.da.UpdateCursor(fc, ['SHAPE@']) as cursor:
    for geom, in cursor:
        geom = arcpy.FromWKT(geom.WKT)
        cursor.updateRow([geom])

This will modify your data in-place, so make sure to have a backup.

Answer 2

It occurred to me that, in my case, I might not actually need to check if a polyline has true curves or not.

My scenario is: I only want to densify segments that are true curves. But I think I can do that by applying densify() to all lines (with curve(s) or not). The trick to not densifying lines without curves (or straight segments within lines with curves) might just be to use densify() properly.

densify (type, distance, deviation)

• TYPE: ANGLE
• DISTANCE: a really big number that would never happen, like 10,000 metres.
  • Is there a reason this argument isn't optional?
• Deviation: 0.174533 radians (10 degrees)

polyline.densify ("ANGLE", 10000, 0.174533)

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I'm not 100% sure if that actually is the proper way to use densify() for true curves. Would welcome corrections.