Yeah, that is a tricky one. There may be some specialty drafting plug-in out there that would do logarithmic scaling, but I would not hold my breath. Sounds like you want to make a slinky type wave form shape....

You might investigate the Distortion envelopes in Illustrator. You might be able take a sine wave with the Zig Zag effect, and distort parts of it with the Object/Distort/Mesh Envelope to squeeze a portion to narrower waves. I tried it, and it seemed to work visually, if not mathematically.

This might be something you could accomplish in After Effects, but that is more like animated Photoshop, not Illustrator.

Britt

On 8/7/18 3:18 PM, Karen Ackoff wrote:
[log in to unmask]"> Marj,

What I would do is make vertical guides spaced as required to establish wave duration. Then I’d create a serpentine path and snap the points to the vertical guides. 

Hard to describe so I hope that’s clear. 

K

>From my iPhone. 

On Aug 7, 2018, at 11:56 AM, Marjorie Leggitt <[log in to unmask]> wrote:

Hey everyone,

I have an AI question: How do you make a longitudinal wave with variable distances between the wave? The wave graduates back and forth between tight waves to move open waves.

Thank for your help.

Marj

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