How to handle duplicate item association in entity?

[vanowm]

Hello.

 

Some entities have duplicate item association in it's list (sorry don't know the proper term).

i.e. a ruled surface is:

((-1 . <Entity name: 4008eaa0>) (0 . "POLYLINE") (330 . <Entity  name: 4008ccd0>) (5 . "E7A4") (100 . "AcDbEntity") (67 . 0) (410 .  "Model") (8 . "MESH") (100 . "AcDbPolygonMesh") (66 . 1) (10 0.0 0.0  0.0) (70 . 16) ... )
[0] (-1 . <Entity name: 4008eaa0>)
[1] (0 . "POLYLINE")
[2] (330 . <Entity name: 4008ccd0>)
[3] (5 . "E7A4")
[4] ([color=red][b]100[/b][/color] . "AcDbEntity")
[5] (67 . 0)
[6] (410 . "Model")
[7] (8 . "MESH")
[8] ([color=red][b]100[/b][/color] . "AcDbPolygonMesh")
[9] (66 . 1)
[10] (10 0.0 0.0 0.0)
[11] (70 . 16)
[12] (40 . 0.0)
[13] (41 . 0.0)
[14] (210 0.0 0.0 1.0)
[15] (71 . 2)
[16] (72 . 13)
[17] (73 . 0)
[18] (74 . 0)
[19] (75 . 0)

Using assoc command returns only the first found association item.

i.e.

(print (assoc 100 (ENTGET (CAR (ENTSEL)))))

Would return

([color=red][b]100[/b][/color] . "AcDbEntity")

but not

([color=red][b]100[/b][/color] . "AcDbPolygonMesh")

Two questions:

1) Is there a command that would return a list of all matched associations or we we have to go through entire list and search each item individually?

 

2) is there a way filter entities by such duplicate associations in (ssget), i.e. this doesn't work:

(SSGET '((100 . "AcDbPolygonMesh")))

It allows select anything instead of only surfaces/meshes.

 

Thank you.

[hanhphuc]

hi have a look dxf reference here

(ssget'((0 . "POLYLINE")(70 . [color="red"]16[/color])))

[Lee Mac]

1) Is there a command that would return a list of all matched associations or we we have to go through entire list and search each item individually?

 

Consider a 'massoc' function to retrieve all items with a given key in an association list.

 

 

2) is there a way filter entities by such duplicate associations in (ssget), i.e. this doesn't work:

(SSGET '((100 . "AcDbPolygonMesh")))

It allows select anything instead of only surfaces/meshes.

 

hi have a look dxf reference here

(ssget'((0 . "POLYLINE")(70 . [color="red"]16[/color])))

 

A good suggestion, however, since DXF group 70 is bit-coded, I would suggest using a Bitwise Masked Equals operator (reference), e.g.:

(ssget '((0 . "POLYLINE") (-4 . "&=") (70 . 16)))

[hanhphuc]

Consider a 'massoc' function to retrieve all items with a given key in an association list.

 

A good suggestion, however, since DXF group 70 is bit-coded, I would suggest using a Bitwise Masked Equals operator (reference), e.g.:

(ssget '((0 . "POLYLINE") (-4 . "&=") (70 . 16)))

 

Thank you Lee for the bonus guide! Noted!

[Lee Mac]

You're welcome!

[vanowm]

Perfect! Thank you very much