incremental and decremental series : How to ?

Hi I'm quite new in grasshopper.

I have a curve and it spin around an axis moving in Z axis ( this create kind of a ribbon ) .... I just do it with a series on Z vector of the move of the curve.

Now I want to move each of this curves incremental of a value in X vector for the half of the value of the number of the curve ( set already on a slider ) than decrement for the same incremental value.

How can I do it ?

As you can see in the picture attached I have already create a working definition and the X moving vector work pretty good ... but always increment.

I just need to interrupt or invert its behaviour from the half of the Flange count so every time I move the flange count slider ... the curve move out for the first half of the series and then in for the second half.

Thank you everybody for the help

Attachments:

1.jpg, 1.8 MB

Replies to This Discussion

Permalink Reply by Marios Tsiliakos on June 26, 2015 at 3:30am

can you provide a sketch?

Permalink Reply by simbiosi on June 26, 2015 at 3:31am

it's attached on a Jpg ... can you see it ?

Permalink Reply by simbiosi on June 29, 2015 at 8:46am

does anybody can help me ?

Permalink Reply by Joseph Oster on June 29, 2015 at 9:10am

Can you post your GH code?

Permalink Reply by simbiosi on June 29, 2015 at 9:12am

off course

Attachments:

Spinning Curves.gh, 16 KB

Permalink Reply by Joseph Oster on June 29, 2015 at 9:43am

Not sure this is what you expected? A smoother transition from plus to minus (1 to -1) might look better?

Attachments:

SpinningCurves_2015Jun29a.gh, 19 KB

Permalink Reply by simbiosi on June 29, 2015 at 9:48am

No ... this isn't what I want .....

I just need that my previous form .... each curves need to increment moving in X .. like I already did ... but ... in the half ... they need to decrement.

Permalink Reply by Joseph Oster on June 29, 2015 at 10:45am

Oh yes, of course. Very nice. Here you go:

Attachments:

SpinningCurves_2015Jun29c.gh, 18 KB

Permalink Reply by Joseph Oster on June 29, 2015 at 11:26am

Weird! My changes got lost before I uploaded the file - was helpful that I took a picture! Restored GH code attached.

Attachments:

SpinningCurves_2015Jun29c.gh, 24 KB

Permalink Reply by J-P on June 29, 2015 at 11:17am

Have you tried reversing the list and then either use merge or insert items to effectively mirror the items?

(bear in mind you may have to cull index 0 or you may get duplicate items on top of each other) does that sound about right?

Permalink Reply by simbiosi on June 29, 2015 at 12:45pm

This was I was intended to do .... but I cannot do it ... I tried but something missing. could you be more precise ? or make an example ?

Permalink Reply by Joseph Oster on June 29, 2015 at 11:53am

Here's one that uses a sine curve to smooth the reversal, which is particularly noticeable in the top view (the sine wave version in blue is enveloping earlier versions):