Simple Math question

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Hi I am trying to learn houdini starting with VOPS sometimes math goes over my head.

I am making a Sine Wave out of a line of points I am adding a Multiply constant node before the Sine that basically multiplies the amount of waves...when I add an ADD constant node it doesn't add more waves instead it offsets the sine waves no matter how big the number.. Is the sine node able to distinguish between add and multiply and treat them differently? I was expecting the add node to add waves just less of them than the multiply but it offsets the sine?

thx
Edited by tsiwt - June 8, 2021 15:23:01
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you should at least post your file to show where you're up to...who cares if people might laugh ? Stuff them, a beginner has to start somewhere.

(you could also put 2*$PI in the length of the line too, just fool around, foolin' around can lead to many happy accidents)
Edited by vusta - June 8, 2021 19:41:48

Attachments:
vu_Freq.hipnc (107.9 KB)

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here is a video there is more vectoring and triangulation needed on your part as the sin node is using radians as input so to get it to function on your points right your going to need to watch this video as it goes into good detail.

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Yes my file is similar to your file if you use an add constant after multiply you will get the behaviour where
the add constant offsets the sine while the multiply constant multiplies the waves...
thank you for your help by the way



Image Not Found
Edited by tsiwt - June 8, 2021 21:14:25

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vops_addvsmultiply.hiplc (146.7 KB)
add vs multiply.JPG (99.4 KB)

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Hi,

If you wanna add more waves, i.e. modify frequency you can modify the yellow node. Am I missing something?

Senior FX TD @ Industrial Light & Magic
Get to the NEXT level in Houdini & VEX with Pragmatic VEX! [www.pragmatic-vfx.com]

youtube.com/@pragmaticvfx | patreon.com/animatrix | animatrix2k7.gumroad.com
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HI animatrix I just want to understand why.. the add node offsets the sine wave while the multiply adds more waves, would't the add also add more waves just less than the multiply?
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Oh I see. The add operation is basically offsetting the waves because adding doesn't scale the point positions it just moves them like 1 becomes 1+x, 2 becomes 2+x, 10 10+x, but their relationship to each other is still the same, compared to multiplication which indeed scales the point positions and therefor the frequency of the waves changes as a whole.
Senior FX TD @ Industrial Light & Magic
Get to the NEXT level in Houdini & VEX with Pragmatic VEX! [www.pragmatic-vfx.com]

youtube.com/@pragmaticvfx | patreon.com/animatrix | animatrix2k7.gumroad.com
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Ohhh wow, now that makes sense. Such a simple concept to understand yet so complex!
Thank You so much,

If you ever make a Pragmatic Vop series of tutorials lmk as I want to use vops instead of vex!

thx again
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tsiwt
Ohhh wow, now that makes sense. Such a simple concept to understand yet so complex!
Thank You so much,

If you ever make a Pragmatic Vop series of tutorials lmk as I want to use vops instead of vex!

thx again

Yes will let you know, or you can use the Snippet VOP in the mean time
Senior FX TD @ Industrial Light & Magic
Get to the NEXT level in Houdini & VEX with Pragmatic VEX! [www.pragmatic-vfx.com]

youtube.com/@pragmaticvfx | patreon.com/animatrix | animatrix2k7.gumroad.com
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