What Is the Y-Axis Scale That Transforms Sine Waves into Straight Lines?

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Discussion Overview

The discussion revolves around identifying the Y-axis scale that would transform a sine or cosine wave into a straight-lined sawtooth pattern, exploring whether such a graphing style exists and if it has a specific name. The conversation touches on concepts from Fourier analysis and the characteristics of triangular waves.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant inquires about the Y-axis scale that would make a sine wave appear as a triangular wave, seeking a specific name for this graphing style.
  • Another participant suggests that the plot type is called a triangular wave and questions if Fourier analysis has been discussed.
  • There is a clarification that while a triangular wave is a good description, the discussion specifically concerns the transformation of a sine wave, not the triangular wave itself.
  • One participant proposes a mathematical representation for the Y-axis scale as y_{scaled}=\sin^{-1}{y_{real}}, indicating that it would not be applicable for values beyond the range of -1 to +1.
  • Another participant mentions familiarity with triangular waves from electrical engineering labs, reinforcing the terminology used.
  • There is a distinction made between a triangular wave created from multiple sine waves and the concept of adjusting the Y-axis scale to represent a single sine wave as triangular.
  • A participant expresses the need to create a custom scale for plotting and comparing statistical results involving sine functions.
  • One participant provides a Fourier series representation for a triangular wave, but another clarifies that this is not relevant to the single frequency sine wave being discussed.
  • Confusion is noted regarding the distinction between a triangular wave and the proposed Y-axis transformation for a sine wave.

Areas of Agreement / Disagreement

Participants express differing views on the terminology and concepts related to the transformation of sine waves into triangular representations. There is no consensus on a specific name for the Y-axis scale or the nature of the transformation.

Contextual Notes

Limitations include the lack of clarity on the mathematical properties of the proposed Y-axis scale and its applicability beyond the range of -1 to +1. The discussion also reflects varying interpretations of triangular waves and their relationship to sine waves.

Who May Find This Useful

This discussion may be of interest to those exploring wave transformations, Fourier analysis, and graphical representations in physics and engineering contexts.

RandallB
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What would you call the scale on the Y axis that would plot a sine or cosine wave as a straight lined saw tooth pattern?

Is such a graphing style in use and does it have a name?
RB
 
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The type of plot to which you are referring is called a Triangular Wave... has your instructor(s) talked about Fourier anaylsis?
 
Theelectricchild said:
The type of plot to which you are referring is called a Triangular Wave... has your instructor(s) talked about Fourier anaylsis?
The type of plot to which you are referring is called a Triangular Wave... has your instructor(s) talked about anaylsis?[/QUOTE]

I can see where Triangular Wave is a good description of what a saw tooth pattern looks like, (of course it's not really a Triangular Wave we are talking about a sine wave here). But did your instructor(s) give a name to the Vertical Scale against the 'angular' Horizontal Scale that causes a Sine Wave plotted with it to appear as a Triangular Wave? Or a name to the type of graph or plot this would be called?

Your not calling it a Fourier Graph or Fourier Plot are you?

I'm only assuming, but it seems to me it would only valid from -1 to +1, that is it would not be "scalable" for use with larger numbers (as a log graph is). Rather the data would need to be scaled to a max of 1.

RB
 
I've never heard of this type of scale, so I can't give you a name.

You are referring to [tex]y_{scaled}=\sin^{-1}{y_{real}}[/tex], correct?

Yes, in that case, it could not directly be expanded to y>1.
 
I know what your talking about, we looked at those kind of waves in E&M when doing voltage analysis in lab. The instructor called them triangle waves.
 
Moo Of Doom said:
I've never heard of this type of scale, so I can't give you a name.
You are referring to [tex]y_{scaled}=\sin^{-1}{y_{real}}[/tex], correct?
Yes, in that case, it could not directly be expanded to y>1.
Yes

I'll keep looking a bit but I'm guessing I'll have to create my own.
I'm thinking it would be helpful in ploting and comparing statistical results involving sin functions.
RB
 
I don't know if you're this far, but even using Matlab or Mathematica will allow you to make use of the following Fourier series for the triangular wave.

[tex]f(t)={\frac{8A}{\pi^2}}\sum_{n=1,3,5,...}^{\infty}[\frac{1}{n^2}sin(\frac{n\pi}{2})]sin(n{\omega_0}t)[/tex]

Where A of course is referring to the amplitude.
 
Theelectricchild said:
I don't know if you're this far, but even using Matlab or Mathematica will allow you to make use of the following Fourier series for the triangular wave.
NO - I believe what your describing is a near infinite number of frequencies or waves to produce a triangular wave (Same kind of thing required for a square wave).

What I have is one wave of only one frequency. I’m just plotting it so that the PLOT is triangular by finding the appropriate Y axis scale.
Thus a Triangular plot here is not the same as a triangular wave.
 
There seems to be a lot of confusion here, so hopefully to clear things up:

He's not talking about infinitely many sine waves being added to make a triangle wave, he is asking about changing the scale of the y-axis to make a single sine wave appear to be a triangular wave. This is analogous to the way a log plot makes an exponential graph appear linear.
 
  • #10
Explain!
 

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