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Mister Spy & Souheyl Bypass Shell

import Base: digamma, Math.@horner
function digamma(z::Complex{Float64})
    # Based on eq. (12), without looking at the accompanying source code, of:
    #     K. S. Kölbig, "Programs for computing the logarithm of the gamma function,
    #     and the digamma function, for complex argument," Computer Phys. Commun.
    #     vol. 4, pp. 221–226 (1972).
    x, y = reim(z)
    if x < 0 # reflection formula
        ψ = -π * cot(π*z)
        x = 1 - x; y = -y
        z = Complex(x, y)
    else
        ψ = zero(z)
    end
    if x < 7 # shift using recurrence formula
        n = 7 - ifloor(x)
        for ν = 0:n-1
            ψ -= inv(z + ν)
        end
        z = Complex(x + n, y)
    end
    t = inv(z)
    ψ += log(z) - 0.5*t
    t *= t # 1/z^2
    ψ -= t * @horner(t,0.08333333333333333,-0.008333333333333333,0.003968253968253968,-0.004166666666666667,0.007575757575757576,-0.02109279609279609,0.08333333333333334) 
end
digamma{T <: Integer}(z::Complex{T}) = digamma(float(z))