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Re: Transforming a polynomial into a trigonometric format tia sal2

• To: mathgroup at smc.vnet.net
• Subject: [mg88234] Re: [mg88207] Transforming a polynomial into a trigonometric format tia sal2
• From: "W_Craig Carter" <ccarter at mit.edu>
• Date: Tue, 29 Apr 2008 06:48:52 -0400 (EDT)
• References: <200804280839.EAA05988@smc.vnet.net>

Hello Tia,
I don't think what you are trying to do is possible, but you may be
able to find approximation methods to get close.

Possible methods include:
a) Truncated Fourier Series, (FourierTrigSeries)
b) Expanding a trignometric function in a series, and then comparing
coefficients
(Series, Collect, Solve)
c) Fit data generated by your model polynomial to your trigonometric form.
(Table, FindFit)

Best Wishes, Craig
On Mon, Apr 28, 2008 at 4:39 AM,  <ratullochjk2 at gmail.com> wrote:

>  I'm using mathematica 6 and I have a polynomial and would like to
>  convert it into
>  a Trigonometric format.  Is this possible?
>
>  Example:
>  I have a polynomial
>  0.00154991- 4.01371 x + 1.81197 x^2 + 8.00183 x^3 - 9.3462 x^4
>
>  How can I transform this into a trigonometric format
>  Example:
>  0.00596679 Cos[6.98132 x] + 0.00358397 Cos[7.21403 x] +
>   2.25013 Sin[0.232711 x] - 4.51511 Sin[0.465421 x]

• References:
  • Transforming a polynomial into a trigonometric format tia sal2
    • From: ratullochjk2@gmail.com