My Math Forum Sine wave question

 Trigonometry Trigonometry Math Forum

 September 19th, 2010, 07:20 AM #1 Newbie   Joined: Sep 2010 Posts: 2 Thanks: 0 Sine wave question Hello, My name is Driehoek and I'm new to this forum. To learn the math involved I'm programming a software synthesizer. I can't find the answer for one problem though: Let's say I have a function that desribes a sine-wave making one rotation per unit: [color=#FF0000]f(x) = (sin (x * pi * 2))[/color] I then want a wave that rotates 4 times per unit, I simply do: [color=#FF0000]h(x) = f(x * 4)[/color] My problem comes if I want to shift the frequency of the wave from i.e. 4 to 0: First I thought I'd make just a function describing the shift: [color=#FF0000]g(x) = 4 - x[/color] and then simply plug it into the wave function: [color=#FF0000]h(x) = f(x * g(x))[/color] The result of this is an undesired one however (the frequency goes down and then up again) this is presumably because "x * g(x)" describes an inverted parabola. ...so finally the question, can somebody hint me, answer me or explain me how to create a sine wave slowly shifting from one frequency to another? This a been troubling me for over a week. I Thank you, Driehoek
 September 19th, 2010, 09:47 AM #2 Newbie   Joined: Sep 2010 Posts: 2 Thanks: 0 Re: Sine wave question I think I solved it myself: h(x) = f((x * a * (d - x)) + (x * b * x) / d) where: a is the starting frequency, b is the ending frequency and d is the duration of the wave.

 Tags question, sine, wave

 Thread Tools Display Modes Linear Mode

 Similar Threads Thread Thread Starter Forum Replies Last Post Luk4 Calculus 7 October 3rd, 2013 01:07 PM HypoXic5665 Applied Math 1 April 2nd, 2013 11:39 PM deedee Trigonometry 6 January 21st, 2013 09:33 AM smash Trigonometry 9 January 4th, 2011 05:29 PM blazingclaymore Computer Science 0 February 5th, 2008 01:01 PM

 Contact - Home - Forums - Cryptocurrency Forum - Top