roots_helper< CC, UU, SS > Struct Template Reference

#include <fft_naive.hpp>

List of all members.

Classes

• struct fft_mul_sc_op

Public Types

• typedef CC C
• typedef UU U
• typedef SS S

Static Public Member Functions

• static U * create_roots (nat n)
• static void destroy_roots (U *u, nat n)
• static void fft_cross (C *c1, C *c2)
• static void dfft_cross (C *c1, C *c2, const U *u)
• static void ifft_cross (C *c1, C *c2, const U *u)
• static void dtft_cross (C *c1, C *c2)
• static void dtft_cross (C *c1, C *c2, const U *u)
• static void itft_flip (C *c1, C *c2, const U *u)
• static void itft_flip (C *c1, C *c2)

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Detailed Description

template<typename CC, typename UU, typename SS>
struct mmx::roots_helper< CC, UU, SS >

Definition at line 24 of file fft_naive.hpp.

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Member Typedef Documentation

typedef CC C

Definition at line 25 of file fft_naive.hpp.

typedef SS S

Definition at line 27 of file fft_naive.hpp.

typedef UU U

Definition at line 26 of file fft_naive.hpp.

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Member Function Documentation

static U* create_roots

(

nat

n

)

[inline, static]

Definition at line 30 of file fft_naive.hpp.

References mmx::bit_mirror().

                       {
    nat k= primitive_root_max_order<C> (2); (void) k;
    VERIFY (k == 0 || n <= k, "maximum order exceeded");
    VERIFY (n >= 2, "size must be at least two");
    U* roots= mmx_new<U> (n);
    for (nat i=0; i<n; i+=2) {
      U temp = primitive_root<C> (n, bit_mirror (i, n));
      roots[i] = temp;
      roots[i+1]= primitive_root<U> (n, i==0? 0: n - bit_mirror (i, n));
    }
    return roots; }

static void destroy_roots	(	U *	u,
		nat	n
	)		[inline, static]

Definition at line 43 of file fft_naive.hpp.

                              {
    mmx_delete<U> (u, n); }

static void dfft_cross	(	C *	c1,
		C *	c2,
		const U *	u
	)		[inline, static]

Definition at line 53 of file fft_naive.hpp.

Referenced by roots_helper< CC, UU, SS >::dtft_cross().

                                        {
    C temp= (*u) * (*c2);
    *c2   = (*c1) - temp;
    *c1   = (*c1) + temp; }

static void dtft_cross	(	C *	c1,
		C *	c2,
		const U *	u
	)		[inline, static]

Definition at line 72 of file fft_naive.hpp.

References roots_helper< CC, UU, SS >::dfft_cross(), and mmx::invert().

                                        {
    static S h= invert (S (2));
    dfft_cross (c1, c2, u);
    *c1 *= h;
    *c2 *= h; }

static void dtft_cross	(	C *	c1,
		C *	c2
	)		[inline, static]

Definition at line 65 of file fft_naive.hpp.

References roots_helper< CC, UU, SS >::fft_cross(), and mmx::invert().

                            {
    static S h= invert (S (2));
    fft_cross (c1, c2);
    *c1 *= h;
    *c2 *= h; }

static void fft_cross	(	C *	c1,
		C *	c2
	)		[inline, static]

Definition at line 47 of file fft_naive.hpp.

Referenced by roots_helper< CC, UU, SS >::dtft_cross().

                           {
    C temp= (*c2);
    *c2   = (*c1) - temp;
    *c1   = (*c1) + temp; }

static void ifft_cross	(	C *	c1,
		C *	c2,
		const U *	u
	)		[inline, static]

Definition at line 59 of file fft_naive.hpp.

                                        {
    C temp= *c2;
    *c2   = (*u ) * ((*c1) - temp);
    *c1   = (*c1) + temp; }

static void itft_flip	(	C *	c1,
		C *	c2,
		const U *	u
	)		[inline, static]

Definition at line 79 of file fft_naive.hpp.

References mmx::invert().

                                       {
    static S h= invert (S(2));
    C temp= (*u) * (*c2);
    *c1  += (*c1) - temp;
    *c2   = h * ((*c1) - temp); }

static void itft_flip	(	C *	c1,
		C *	c2
	)		[inline, static]

Definition at line 86 of file fft_naive.hpp.

References mmx::invert().

                           {
    static S h= invert (S(2));
    *c1  += (*c1) - (*c2);
    *c2   = h * ((*c1) - (*c2)); }

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The documentation for this struct was generated from the following file:

• /Users/mourrain/Devel/mmx/algebramix/include/algebramix/fft_naive.hpp