Selecting surfaces

Hello.
I need your help.

There are two groups of surfaces. The first group has 84 surfaces and the second group has 76 surfaces. All of the second group surfaces are included in the first group. It means that there are 8 surfaces which are not intersected. I want to select the 8 surface in grasshopper.
I have tried “subtract”, “solid difference” but they didn’t work.

again, my purpose is selecting red surfaces without green surfaces in grasshopper. Please, give me some good idea.
Thank you.

selecting surfaces_0515.gh (56.7 KB)

There are 16 surfaces colliding, if that’s what you mean by ‘intersecting’, not 8

What’s probably better is to link your data separation to what’s making the surfaces that would otherwise be identical ‘differ’ in the first place. With what you’ve provided here all one can do quickly is try to find equivalences between your two groups of surfaces.

Not true:

Here’s a work-around:
selecting surfaces_0515.gh (59.6 KB)

Thank you very much.
This is exactly what I wanted.

You are right that the surfaces of the second group are not included in the first group. However, I made the second group from the first group. I used “randomly reduce” to make second group surfaces from the first group. That is why I assumed that the second group is included in the first group.

Anyway, thank you very much again.

selecting surfaces_0515_2.gh (39.2 KB)

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