将如下matlab代码转成C语言代码 function [idx, pow] = getBestIdx(spec, low, high, num, fs, Nfft, step) % step: 指定间隔多少bpm [~, eIdx] = sort(spec(low:high), 'descend'); % 从大到小排序 eIdx = eIdx + low - 1; cnt = 1; res = zeros(1, num); pow = zeros(1, num); for k = 1 : length(eIdx) aa = (eIdx(k) - step : eIdx(k) + step); aa(aa < low) = low; aa(aa > high) = high; aa = spec(eIdx(k)) - spec(aa); if length(find(aa < 0)) == 0 res(1, cnt) = eIdx(k); pow(1, cnt) = spec(eIdx(k)); cnt = cnt + 1; if cnt > num break; end end end idx = res; pow = pow / max(pow);

以下是将该 Matlab 代码转换为 C 语言代码的步骤：

1. 定义函数头和输入参数

void getBestIdx(double *spec, int low, int high, int num, double fs, int Nfft, int step, int *idx, double *pow);

2. 从大到小排序

int len = high - low + 1;
int eIdx[len], idx_sort[len];
for (int i = 0; i < len; i++) {
    eIdx[i] = low + i;
}
for (int i = 0; i < len; i++) {
    idx_sort[i] = i;
}
for (int i = 0; i < len - 1; i++) {
    for (int j = i + 1; j < len; j++) {
        if (spec[eIdx[idx_sort[i]]] < spec[eIdx[idx_sort[j]]]) {
            int tmp = idx_sort[i];
            idx_sort[i] = idx_sort[j];
            idx_sort[j] = tmp;
        }
    }
}

3. 遍历排序后的数组，找到符合条件的元素

int cnt = 0;
double res[num], pow[num];
for (int k = 0; k < len; k++) {
    int aa_low = eIdx[idx_sort[k]] - step;
    int aa_high = eIdx[idx_sort[k]] + step;
    if (aa_low < low) {
        aa_low = low;
    }
    if (aa_high > high) {
        aa_high = high;
    }
    double aa[aa_high - aa_low + 1];
    for (int i = 0; i < aa_high - aa_low + 1; i++) {
        aa[i] = spec[eIdx[idx_sort[k]]] - spec[aa_low + i];
    }
    int flag = 1;
    for (int i = 0; i < aa_high - aa_low + 1; i++) {
        if (aa[i] < 0) {
            flag = 0;
            break;
        }
    }
    if (flag) {
        res[cnt] = eIdx[idx_sort[k]];
        pow[cnt] = spec[eIdx[idx_sort[k]]];
        cnt++;
        if (cnt >= num) {
            break;
        }
    }
}

4. 返回结果

for (int i = 0; i < cnt; i++) {
    idx[i] = res[i];
    pow[i] = pow[i] / max(pow, num);
}