//复数的模，模值*N/2对应该频率下信号的幅度，模值/N直流信号幅度 s1[i].real=sqrtf(s1[i].real*s1[i].real+s1[i].imag*s1[i].imag); s2[i].real=sqrtf(s2[i].real*s2[i].real+s2[i].imag*s2[i].imag); //printf("%d\n",s1[i].real); } s1_max_index=find_max_num_index(s1,60);//最大幅度值为第几个 s2_max_index