void pcshft(double a, double b, double d[], int n)
{
	double const1,fac;
	int j;
    const1 = 2.0 / (b - a);
    fac = const1;
    for (j = 2; j<=n; j++)
	{
        d[j] = d[j] * fac;
        fac = fac * const1;
    }
    const1 = 0.5 * (a + b);
    for (j = 1; j<=n - 1; j++)
	{
        for (int k = n - 1; k>=j; k--)
		{
            d[k] = d[k] - const1 * d[k + 1];
        }
    }
}