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Hey guys I'm new to Blender. I don't know about Sine function in Math Node. Blender's official manual redirects me to the Wikipedia page but in there I don't understand the process. I want to know how to predict the output of the sine function and how it works in Blender.

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    $\begingroup$ Do you know sine from elsewhere? The sine function is exactly like any other sine function: sine(theta) is the Y coordinate of a unit vector as it rotates about the origin by theta radians in an XY coordinate system, starting at 0 radians for a 1,0 +X vector. So the sine of 0 is 0; the sine of pi/2 (90 degrees) is 1 (vector rotated 90 degrees is at 0,1); sine of pi/4 is 2^0.5/2. $\endgroup$
    – Nathan
    Commented Aug 17, 2022 at 5:38
  • $\begingroup$ maybe you have written your question a bit unfortunate...but as Nathan wrote and understood it - your questions sounds like you don't know sin function at all...and if so - than you should post your question in a math forum, not here $\endgroup$
    – Chris
    Commented Aug 17, 2022 at 6:56
  • $\begingroup$ Thank you Chris and Nathan for your support. $\endgroup$ Commented Aug 17, 2022 at 7:00
  • $\begingroup$ I think the OP was just confused on why for example sine(90) would not return 1 as he might have expected. He probably expected the inputs to be degrees but didn't know that Blender's trigo functions use angles in radians instead of degrees $\endgroup$
    – Harry McKenzie
    Commented Aug 17, 2022 at 7:06
  • $\begingroup$ @HarryMcKenzie: that's why he should improve/edit his question to make it clear what exactly his problem is...it's pretty vague so...💁🏻‍♂️ $\endgroup$
    – Chris
    Commented Aug 17, 2022 at 8:29

2 Answers 2

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Sine outputs a number from -1 to 1. You can use the Map Range node afterwards to convert it to any range you want.

To ensure your animation loops seamlessly, add a Map Range node before the sine that outputs 0 to 2*pi (you can actually type pi in the max value box and it will accept it).

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    $\begingroup$ Fun fact for geeks... You can also type tau for 2pi $\endgroup$
    – Robin Betts
    Commented Apr 18, 2023 at 18:47
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This plane is slightly wider than 2pi, slightly deeper than 2. It's mapped in its Object coordinates. Its object-origin is at its centre.

enter image description here

The Math > Sine node returns the sine of its input, where the input is in radians.

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    $\begingroup$ What is the domain before it repeats? Slightly wider than 4pi?? $\endgroup$
    – Richard
    Commented Apr 18, 2023 at 17:58
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    $\begingroup$ @Richard ... Yikes! I've got the scale wrong by 2! The period should be 2pi, Correcting it now... $\endgroup$
    – Robin Betts
    Commented Apr 18, 2023 at 18:23
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    $\begingroup$ Yeah, just tested that $\endgroup$
    – Richard
    Commented Apr 18, 2023 at 18:32
  • $\begingroup$ @Richard Thanks.... done now :) $\endgroup$
    – Robin Betts
    Commented Apr 18, 2023 at 18:39

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