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Grouping and Foreach

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winkel
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Hi again,
I have an object with a number of lines inside one SOP and need to build groups. I try to explain:

1. I have:

f.e. A sop with 4 lines

2. I want an output (maybe foreach):

- group1 with Line 1 and 2
- group2 with Line 2 and 3
- group3 with Line 3 and 4

Thanks for help

Detlef
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winkel
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Sorry, I forgot:
this must be full procedural because I have different amounts of lines.
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anon_user_54555117
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I would use a copy/delete combination
null1
a place holder used later
delete1:
Group`stamp(“../copy1”,“line”,0)`
Operation Delete Non-Selected
branch from null1
sort1
Primitive tab
Primitive Sort: Shift
Offset: -1
delete2
Group`stamp(“../copy1”,“line”,0)`
Operation Delete Non-Selected
merge1:
merge both delete1 and delete2
group1
Create tab
Group Name:linegroup`padzero(4, stamp(“../copy1”,“line”,0))`
Number tab
Operation: Group By Pattern
Pattern:0-1
copy1
Copy tab:
Number of copies: nprims(“../null1”)-1
Stamp tab:
check Stamp Inputs
tab 1-10:
Variable 1:line
Value 1:$CY

This should give you a number of group equal to one less than the number of lines feed in.

Using the padzero function gives you a fixed trim value if you want for finding the groupvalue later on.
If you do not want to use the padzero you can replace this line
linegroup`padzero(4, stamp(“../copy1”,“line”,0))`
with
linegroup`stamp(“../copy1”,“line”,0)`
Hope this helps
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winkel
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wonderful! that works!!!!!

Thanks a lot. And what a description…

Have a nice day?
Detlef
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Simon
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Couldn't you just use the partition sop with an expression like this in it

Group`floor($PR/2)`
The trick is finding just the right hammer for every screw
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winkel
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ha, it gives you only pairs with different PR numbers (12, 34) oad not (12, 23, 34)
Maybe there is another expression but I'm too stupid for such math

Thanks
Detlef
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Simon
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Sorry I misunderstood. It gives you what you listed in your first mail.
The trick is finding just the right hammer for every screw
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tamte
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here is an example with foreach if you are interested

Attachments:
group_forEach.hip (47.1 KB)

Tomas Slancik
FX Supervisor
Method Studios, NY
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Simon
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Simon
Sorry I misunderstood. It gives you what you listed in your first mail.

Oh, no it doesn't I misread what you had written. You need each entry to appear in two groups. Sorry

How about this?
Edited by - Dec. 12, 2008 08:56:11

Attachments:
group.hip (37.9 KB)

The trick is finding just the right hammer for every screw
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rdg
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You can actually use two partitionSOPs and a sortSOP to select the pairs you need.
The delete sop deletes all but one group per frame to show the results.

Attachments:
setup_select_12_23_34_45.hip (41.8 KB)

this is not a science fair.
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winkel
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here is my solution with a big help from all of you, special from Mario Marengo

http://www.sidefx.com/index.php?option=com_forum&Itemid=172&page=viewtopic&p=66345#66345 [sidefx.com]

Now I have still trouble with some point normals.

See attached Hip file for building a Line with bows as an first step and

Attachments:
PipeTrouble.jpg (14.5 KB)
Pipes01.hip (144.1 KB)

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