remove duplicate lines

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remove duplicate lines

Post by hvfrancesco » Wed Oct 30, 2019 5:05 pm

I have some issues in cleaning a dxf file I produce from projections of a sketchup model.
Having several stacked lines I use the detect duplicate command, but when I choose to delete the detected duplicates all of the lines are deleted and not only the redundant ones.
I attach one of the files I'm having troubles with.
(451.02 KiB) Downloaded 142 times

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Re: remove duplicate lines

Post by Husky » Wed Oct 30, 2019 7:40 pm

I assume the issue is based on the size of your drawing. It is very tiny with unusual short line entities.

Roof upper left side:

Husky-2019.10.30-01.png (14.52 KiB) Viewed 1896 times

To clean that up effectively you have to adjust the "Distance Tolerance" in the "Detect Duplicate" Option bar or scale the drawing to a more reasonable size.
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Re: remove duplicate lines

Post by CVH » Wed Oct 30, 2019 10:05 pm

The function 'Detect Duplicate' will find duplicates
governed by the given tolerances as far as they:
  • are almost the same
    are almost at the the same position
    have almost the same angle
When the entities differs considerably in lenght or
when they only overlap partially they are not considered as a duplicate.
See example dxf.

Above 0.00045 tolerance most parallel lines of the rooftop are considered as duplicates.
As they are only spaced 0.000085 / 0.000338 / ....

I saw some did protude a little.
With a few simple selects I could isolate some on 5 separete layers.
From what was left I have put the duplicates found apart in layer 6.
Before deleting any it is better to move them to a temporary layer (eg. Trashcan).

It not looking great.
I afraid there is now easy solution.
Revised file attached

(501.39 KiB) Downloaded 120 times
Not duplicates.dxf
(99.39 KiB) Downloaded 122 times

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