Julien Vincenot

I have a little problem with zl in Jitter, but i assume it can interest max and msp-only people...

I use zl to sort (in descending order), a list

example : 12 8 61 4 -30 1 84 -> 84 61 12 8 4 1 -30

Actually i need to do that to have always bigger blobs sizes (detected with cv.jit.blobs.centroids) in first positions in a list, for coll-sampling reasons.

My problem is that i want to synchronize this sorting process with other parameters/planes in a matrix (x/y axes of the blobs): obviously if i sort all my planes separately, all my blobs informations will be mixed up...

What i want i pretty simple to do with LISP in PWGL (position-match) but in Max... : i would just need to reorder a given list by using the indexes given by the 'zl sort' right outlet from another list.

i would like any other list of the same length 

to be reordered according to the indexes like this

The advantage of this kind of process is that i can handle lists with lengths varying over time, taking always the more 'important' values even if it depends of another parameter.

I use zl to sort (in descending order), a list
of parameters from a video analysis.

example : 
from the first example would be 
returned these 'reordered indexes' 

6 2 0 1 3 5 4
i would like any other list of the same length 
for instance 1 2 3 4 5 6 7
to be reordered according to the indexes like this
7 3 1 2 4 6 5

The advantage of this kind of process is that i can handle lists with lengths varying over time, taking always the more 'important' values even if it depends of another parameter.
Do you think it would be possible ?

list-processing-problem-zl-sort-index

Not sure this is what you want, but [coll]'s sort method accepts a "location" argument. So you can sort the [coll] entries using for instance the 3rd data in a row.

I didn't know this part of coll, that's pretty cool, thanks.

Actually my problem is a little bit deeper.

I'm trying to sample many (maximum 30) parameters from the video

in the coll, and the process i need to use can make

For instance : informations about only five blobs (the bigger ones) can reach the coll, otherwise my coll would be really hard to manipulate (I'm using this for time-differed computer-aided composition).

Actually i have just found the 'position' function in the RTC library, but i'm not sure it is so reactive...

Actually my problem is a little bit deeper.
I'm trying to sample many (maximum 30) parameters from the video
in the coll, and the process i need to use can make
the routing of datas easier.

Actually i have just found the 'position' function in the RTC library, but i'm not sure it is so reactive...


Try [zl lookup] using the index outlet from [zl sort]. Here's a small example patch, I think it does what you're asking.

(i must have read the help patches a little too fast...) 

That's exactly what i was looking for
(i must have read the help patches a little too fast...) 
and without using an external library.
That will probably work even better.

List processing problem (zl sort index)