ThresholdNorm

指定常数作为阈值，给向量中的元素做设阈操作。与threshold接口不同的是，不包含relOp参数，比较模式由接口函数名直接指定。包含两类比较模式：

HMPPS_Threshold_LT
小于操作，即level是源向量的下边界。计算公式为：

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若src[n]为复数序列，则

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HMPPS_Threshold_GT
大于操作，即level是源向量的上边界。计算公式为：

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若src[n]为复数序列，则

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函数接口声明如下：

整型数的操作：
HmppResult HMPPS_Threshold_LT_16s(const int16_t* src, int16_t* dst, int32_t len, int16_t level);

HmppResult HMPPS_Threshold_LT_32s(const int32_t* src, int32_t* dst, int32_t len, int32_t level);

HmppResult HMPPS_Threshold_GT_16s(const int16_t* src, int16_t* dst, int32_t len, int16_t level);

HmppResult HMPPS_Threshold_GT_32s(const int32_t* src, int32_t* dst, int32_t len, int32_t level);

浮点数的操作：
HmppResult HMPPS_Threshold_LT_32f(const float* src, float* dst, int32_t len, float level);

HmppResult HMPPS_Threshold_LT_64f(const double* src, double* dst, int32_t len, double level);

HmppResult HMPPS_Threshold_LT_32fc(const Hmpp32fc* src, Hmpp32fc* dst, int32_t len, float level);

HmppResult HMPPS_Threshold_GT_32f(const float* src, float* dst, int32_t len, float level);

HmppResult HMPPS_Threshold_GT_64f(const double* src, double* dst, int32_t len, double level);

HmppResult HMPPS_Threshold_GT_32fc(const Hmpp32fc* src, Hmpp32fc* dst, int32_t len, float level);

整型数的原址操作：
HmppResult HMPPS_Threshold_LT_16s_I(int16_t* srcDst, int32_t len, int16_t level);

HmppResult HMPPS_Threshold_LT_32s_I(int32_t* srcDst, int32_t len, int32_t level);

HmppResult HMPPS_Threshold_GT_16s_I(int16_t* srcDst, int32_t len, int16_t level);

HmppResult HMPPS_Threshold_GT_32s_I(int32_t* srcDst, int32_t len, int32_t level);

浮点数的原址操作：
HmppResult HMPPS_Threshold_LT_32f_I(float* srcDst, int32_t len, float level);

HmppResult HMPPS_Threshold_LT_64f_I(double* srcDst, int32_t len, double level);

HmppResult HMPPS_Threshold_LT_32fc_I(Hmpp32fc* srcDst, int32_t len, float level);

HmppResult HMPPS_Threshold_GT_32f_I(float* srcDst, int32_t len, float level);

HmppResult HMPPS_Threshold_GT_64f_I(double* srcDst, int32_t len, double level);

HmppResult HMPPS_Threshold_GT_32fc_I(Hmpp32fc* srcDst, int32_t len, float level);

参数

参数名	描述	取值范围	输入/输出
src	指向源向量的指针。	非空	输入
dst	指向目标向量的指针。	非空	输出
srcDst	指向原址操作向量的指针。	非空	输入/输出
len	向量长度。	(0, INT_MAX]	输入
level	阈值。	不限，视类型而定	输入

返回值

成功：返回HMPP_STS_NO_ERR。
失败：返回错误码。

错误码

错误码	描述
HMPP_STS_NULL_PTR_ERR	src、dst、srcDst这几个入参中存在空指针。
HMPP_STS_SIZE_ERR	len小于或等于0。
HMPP_STS_THRESH_NEG_LEVEL_ERR	阈值小于0。

示例

#define BUFFER_SIZE_T 20

void ThresholdNormExample(void)
{
    float src[BUFFER_SIZE_T] = {4.52,  5.92, 6.15, 8.17,  9.93,  6.04, 11.17, 2.79, 3.58, 0.71,
                                -0.15, 9.68, 9.13, 11.04, 10.37, 0.21, 7.47,  0.05, 2.33, -1.58};
    float dst1[BUFFER_SIZE_T] = {0.00};
    float dst2[BUFFER_SIZE_T] = {0.00};
    HmppResult result;
    result = HMPPS_Threshold_LT_32f(src, dst1, BUFFER_SIZE_T, 3.14);
    printf("Threshold1: result = %d\n", result);
    if (result != HMPP_STS_NO_ERR) {
        return;
    }
    printf("dst1 =");
    for (int i = 0; i < BUFFER_SIZE_T; i++) {
        printf(" %.2f", dst1[i]);
    }
    result = HMPPS_Threshold_GT_32f(src, dst2, BUFFER_SIZE_T, 3.14);
    printf("\nThreshold2: result = %d\n", result);
    if (result != HMPP_STS_NO_ERR) {
        return;
    }
    printf("dst2 =");
    for (int i = 0; i < BUFFER_SIZE_T; i++) {
        printf(" %.2f", dst2[i]);
    }
    printf("\n");
}

运行结果：

Threshold1: result = 0
dst1 = 4.52 5.92 6.15 8.17 9.93 6.04 11.17 3.14 3.58 3.14 3.14 9.68 9.13 11.04 10.37 3.14 7.47 3.14 3.14 3.14
Threshold2: result = 0
dst2 = 3.14 3.14 3.14 3.14 3.14 3.14 3.14 2.79 3.14 0.71 -0.15 3.14 3.14 3.14 3.14 0.21 3.14 0.05 2.33 -1.58

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