數(shù)據(jù)結(jié)構(gòu)算法:龍貝格積分法

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估計(jì)很多人對(duì)龍貝格積分法不是很連接吧，下面我一起來看看龍貝格積分法代碼：
    #include
    #include
    #define eps 0.0000001
    #define max 20
    double f(double x)
    {
    if(x==0)
    return 1;
    else
    return (sin(x)/x);
    }
    void romberg(double a,double b)
    {
    double t[max][4]={0},h=1.0,e=1.0+eps;
    double fnew;
    int i,j,k=1,m;
    t[0][0]=h*(f(a)+f(b))/2.0;
    while((keps))
    {
    fnew=0;
    for(i=1;i<=(int)(pow(2,k-1));i++)
    fnew=fnew+f(a+(i-0.5)*h);
    t[k][0]=(t[k-1][0]+h*fnew)/2.0;
    for(m=1;m<=k;m++)
    {
    if(m>3)
    break;
    t[k][m]=(pow(4,m)*t[k][m-1]-t[k-1][m-1])/(pow(4,m)-1);
    }
    if(k>=4)
    e=fabs(t[k][3]-t[k-1][3]);
    k++;
    h=h/2.0;
    }
    if(k>max)
    printf(\"method failed.\\n\");
    else
    {
    printf(\"\\tt\\t\\ts\\t\\tc\\t\\tr\\n\");
    for(i=0;i    {
    printf(\"k=%d\\t\",i);
    for(j=0;j<4;j++)
    if(i>=j)
    printf(\"%0.9lf\\t\",t[i][j]);
    printf(\"\\n\");
    }
    }
    }
    int main()
    {
    double a=0.0,b=1.0;
    romberg(a,b);
    return 0;
    }