c语言1 qnan,运行程序时变量值为1.#QNAN是怎么回事？

我刚用C6711的simulator试了一下,使用dsp67x.lib, 从TI的网站下载sprc121.zip解压缩之后就有这个库文件. 当调用DSPF_sp_biquad时只要最后一个参数(滤波的点数)不是3的倍数,程序就从那个函数里出不来.

#include

#include "dspf_sp_biquad.h"

float B[] = {1.0, 0, 0};

float A[] = {0, 0};

float inbuf[128];

float outbuf[128];

float delay[2];

void main(void)

{

int i, j;

float *pIn, *pB, *pA, *pDly, *pOut;

int cnt;

cnt = 128;

for (i=0; i

{

inbuf[i] = i+1;

outbuf[i] = 0.0;

}

delay[0] = 0.;

delay[1] = 0.;

pIn = inbuf;

pB  = B;

pA  = A;

pDly = delay;

pOut = outbuf;

DSPF_sp_biquad(pIn, pB, pA, pDly, pOut, 3);

j = cnt;

}

TI的DSPF_sp_biquad函数C程序如下:

void DSPF_sp_biquad    (

float x[],         //Pointer to input samples</