kml_fft(f/h)_plan_guru64_r2r
建立多组数据序列n维R2R变换的plan。其中,单个FFT的数据序列不需要是连续的,可以以跨步的形式提供。与kml_fft_plan_guru_dft不同的是,kml_fft_plan_guru64_dft允许部分参数是64位的整型。
接口定义
kml_fft_plan kml_fft_plan_guru64_r2r(int rank, const kml_fft_iodim64 *dims, int howmany_rank, const kml_fft_iodim64 *howmany_dims, double *in, double *out, const kml_fft_r2r_kind *kind, unsigned flags);
kml_fftf_plan kml_fftf_plan_guru64_r2r(int rank, const kml_fftf_iodim64 *dims, int howmany_rank, const kml_fftf_iodim64 *howmany_dims, float *in, float *out, const kml_fftf_r2r_kind *kind, unsigned flags);
kml_ffth_plan kml_ffth_plan_guru64_r2r(int rank, const kml_ffth_iodim64 *dims, int howmany_rank, const kml_ffth_iodim64 *howmany_dims, __fp16 *in, __fp16 *out, const kml_ffth_r2r_kind *kind, unsigned flags);
Fortran interface:
RES = KML_FFT_PLAN_GURU64_DFT_R2R(RANK, DIMS, HOWMANY_RANK, HOWMANY_DIMS, IN, OUT, KIND, FLAGS);
RES = KML_FFTF_PLAN_GURU64_DFT_R2R(RANK, DIMS, HOWMANY_RANK, HOWMANY_DIMS, IN, OUT, KIND, FLAGS);
RES = KML_FFTH_PLAN_GURU64_DFT_R2R(RANK, DIMS, HOWMANY_RANK, HOWMANY_DIMS, IN, OUT, KIND, FLAGS);
KML_FFT_REDFT11和KML_FFT_RODFT11只支持长度为4的整数倍大小的序列,其他变换类型只支持长度为2的整数倍大小的序列。
返回值
函数返回一个kml_fft(f/h)_plan类型的结构体指针。将该对象作为参数传入kml_fft(f/h)_execute函数中使用,将对当前提供的输入in和输出out执行FFT变换;另外,也可以通过将该对象作为参数传入kml_fft(f/h)_execute_r2r函数中以对新的输入in和输出out执行FFT变换。
如果函数返回非空指针,则表示plan执行成功,否则表示执行失败。
参数
| 参数名 | 数据类型 | 描述 | 输入/输出 | 
|---|---|---|---|
| rank | int | 单个FFT序列的维度。 约束:1 ≤ rank ≤ 3。 | 输入 | 
| dims | 
 | dims是大小为rank的结构体数组,dims[i]包含以下成员: 
 约束:dims[i].n ≥ 1, for i in 0 to rank - 1。 | 输入 | 
| howmany_rank | int | 多个rank维FFT之间的内存排布用howmany_rank维的howmany_dims数组来描述,howmany_rank表示每个要计算的rank维FFT变换的起始地址的内存访问模式所需的维数。 约束:0 ≤ howmany_rank ≤ 3。 | 输入 | 
| howmany_dims | 
 | howmany_dims是大小为howmany_rank的结构体数组,howmany_dims[i]包含以下成员: 
 | 输入 | 
| in | 
 | 输入待变换的数据。 | 输入 | 
| out | 
 | 输出快速傅里叶变换后的数据。 | 输出 | 
| kind | 
 | kind是大小为rank的数组,包含FFT序列每一维度的R2R变换类型,kind[i] (for i in 0 to rank - 1)有以下可选值: 
 | 输入 | 
| flags | unsigned int | planning选项,描述ESTIMATE模式或PATIENT模式。 KML_FFT_ESTIMATE:ESTIMATE模式 KML_FFT_PATIENT:PATIENT模式 | 输入 | 
依赖
C: "kfft.h"
示例
C interface:
    int rank = 2; 
    kml_fft_iodim64 *dims; 
    dims = (kml_fft_iodim64*)kml_fft_malloc(sizeof(kml_fft_iodim64) * rank); 
    dims[0].n = 2; 
    dims[0].is = 2; 
    dims[0].os = 2; 
    dims[1].n = 2; 
    dims[1].is = 1; 
    dims[1].os = 1; 
    int howmany_rank = 1; 
    kml_fft_iodim64 *howmany_dims; 
    howmany_dims = (kml_fft_iodim64*)kml_fft_malloc(sizeof(kml_fft_iodim64) * howmany_rank); 
    howmany_dims[0].n = 2; 
    howmany_dims[0].is = 2 * 2; 
    howmany_dims[0].os = 2 * 2; 
    double init[8] = {120, 0, 8, 8, 0, 0, 0, 16}; 
    double *in; 
    in = (double*)kml_fft_malloc(sizeof(double) * 8); 
    for (int i = 0; i < 8; i++) { 
        in[i] = init[i]; 
    } 
    double *out; 
    out = (double*)kml_fft_malloc(sizeof(double) * 8); 
    kml_fft_r2r_kind *kind; 
    kind = (kml_fft_r2r_kind*)kml_fft_malloc(sizeof(kml_fft_r2r_kind) * rank); 
    kind[0] = KML_FFT_DHT; 
    kind[1] = KML_FFT_REDFT01; 
    kml_fft_plan plan; 
    plan = kml_fft_plan_guru64_r2r(rank, dims, howmany_rank, howmany_dims, in, out, kind, KML_FFT_ESTIMATE); 
    kml_fft_execute_r2r(plan, in, out); 
 
    kml_fft_destroy_plan(plan); 
    kml_fft_free(howmany_dims); 
    kml_fft_free(dims); 
    kml_fft_free(kind); 
    kml_fft_free(in); 
    kml_fft_free(out); 
 
    /* 
     * out = {1.393137e+02, 1.166863e+02, 1.006863e+02, 1.233137e+02, 
     *        2.262742e+01, -2.262742e+01, -2.262742e+01, 2.262742e+01} 
     */
Fortran interface:
    INTEGER(C_INT) :: RANK = 2 
    INTEGER(C_INT) :: KIND(2) 
    INTEGER(C_INT) :: HOWMANY_RANK = 1 
    TYPE(KML_FFT_IODIM64), POINTER :: DIMS(:), HOWMANY_DIMS(:) 
    REAL(C_DOUBLE), DIMENSION(8) :: INIT 
    TYPE(C_DOUBLE), POINTER :: IN(:), OUT(:) 
    TYPE(C_PTR) :: PIN, POUT, PDIMS, PHOWMANY_DIMS 
    INTEGER(C_SIZE_T) :: SIZE1, SIZE2, SIZE3 
    SIZE1 = 8 * 12 
    SIZE3 = 24 * RANK 
    SIZE4 = 24 * HOWMANY_RANK 
    PDIMS = KML_FFT_MALLOC(SIZE2) 
    PHOWMANY_DIMS = KML_FFT_MALLOC(SIZE3) 
    PIN = KML_FFT_MALLOC(SIZE1) 
    POUT = KML_FFT_MALLOC(SIZE1) 
    CALL C_F_POINTER(PIN, IN, SHAPE=[8]) 
    CALL C_F_POINTER(POUT, OUT, SHAPE=[8]) 
    CALL C_F_POINTER(PDIMS, DIMS, SHAPE=[RANK]) 
    CALL C_F_POINTER(PHOWMANY_DIMS, HOWMANY_DIMS, SHAPE=[HOWMANY_RANK]) 
     
    DIMS(0)%N = 2 
    DIMS(0)%IS = 2 
    DIMS(0)%OS = 2 
    DIMS(1)%N = 2 
    DIMS(1)%IS = 1 
    DIMS(1)%OS = 1 
    HOWMANY_DIMS(0)%N = 2 
    HOWMANY_DIMS(0)%IS = 2 * 2 
    HOWMANY_DIMS(0)%OS = 2 * 2 
    DATA INIT/120, 0, 8, 8, 0, 0, 0, 16/ 
    INTEGER :: I 
    DO WHILE(I <= 8) 
        IN(I) = INIT(I) 
    END DO 
    KIND(0) = KML_FFT_DHT 
    KIND(1) = KML_FFT_REDFT01 
 
    TYPE(C_PTR) :: PLAN 
    PLAN = KML_FFT_PLAN_GURU4_R2R(RANK, DIMS, HOWMANY_RANK, HOWMANY_DIMS, IN, OUT, KIND, KML_FFT_ESTIMATE) 
    CALL KML_FFT_EXECUTE_R2R(PLAN, IN, OUT) 
 
    CALL KML_FFT_DESTROY_PLAN(PLAN) 
    CALL KML_FFT_FREE(PHOWMANY_DIMS) 
    CALL KML_FFT_FREE(PDIMS) 
    CALL KML_FFT_FREE(PIN) 
    CALL KML_FFT_FREE(POUT) 
    ! 
    ! OUT = /1.393137E+02, 1.166863E+02, 1.006863E+02, 1.233137E+02, 
    !        2.262742E+01, -2.262742E+01, -2.262742E+01, 2.262742E+01/ 
    !