PhiMeyer <- function(x)
{
        a <- 0
        if(abs(x) < (2 * 3.14159265)/3)
                a <- 1
        if(abs(x) >= (2 * 3.14159265)/3 && abs(x) <= (4 * 3.14159265)/3)
                a <- cos(3.14159265/2 * NuTaper(0.477464829 * abs(x) - 1))
        return(a)
}


# PhiMeyer uses NuTaper function

NuTaper  <- function(x)
return(x^4 * (35 - 84 * x + 70 * x^2 - 20 * x^3))