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14<h1 align="left">MATH_MakeFFTSinTable<img src="../../image/NTR.gif"align="middle"><img src="../../image/TWL.gif" align="middle"></H1>
15<H2>Syntax</H2>
16
17<dl>
18  <dd>
19  <PRE><CODE>#include &lt;nitro/math/fft.h&gt;
20
21void MATH_MakeFFTSinTable( fx16* sinTable, u32 nShift );
22</CODE></PRE>
23  </dd>
24</dl><h2>Arguments</h2>
25
26<table border="1" width="100%">
27    <TR>
28      <TD width="176"><em><strong><font face="Courier New">sinTable</font></strong></em></TD>
29      <TD width="670">Pointer to the table of sine values.</TD>
30    </TR>
31    <TR>
32      <TD width="176"><em><strong><font face="Courier New">nShift</font></strong></em></TD>
33      <TD width="670">The value obtained by taking the base 2 logarithm for the data length.</TD>
34    </TR>
35  </table>
36<h2>Return Values</h2>
37<p>None.</p>
38<H2>Description</H2>
39<P>
40This creates a sine value table required for fast Fourier transforms.<BR>
41</P>
42<P>
43In the explanation below, the value 2<sup>nShift</sup> (2 to the nShift power) is represented as N. A pointer to an fx16 type array of length of N*3/4 is passed to sinTable. Calling this function causes a fx16 type sin value to be assigned in the sinTable that satisfies <CODE>sinTable[k] = <i>sin</i>( (2&#x3C0;/N) * k )  (k = 0, 1,..., N*3/4-1)</CODE>. In doing so, the <CODE><A href="../../fx/FX_SinIdx.html">FX_SinIdx</A></CODE> function will be used.
44</P>
45<h2>See Also</h2>
46<P><CODE><A href="../../fx/FX_SinIdx.html">FX_SinIdx</A>, <A href="MATH_FFT.html">MATH_FFT</A>, <A href="MATH_IFFT.html">MATH_IFFT</A>, <A href="MATH_FFTReal.html">MATH_FFTReal</A>, <A href="MATH_IFFTReal.html">MATH_IFFTReal</A></CODE></P>
47<H2>Revision History</H2>
48<P>
492005/07/21 Corrected description of <em><strong><CODE>sinTable</CODE></strong></em>.<br /> 2005/05/13 Initial version.
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