DNDA.jl

function DNDA(ALPHA,BETA);
      A=[0.0010    0.0020   -0.0060   -0.0110   -0.0150   -0.0240   -0.0220
        -0.0270   -0.0140   -0.0080   -0.0110   -0.0150   -0.0100    0.0020
        -0.0170   -0.0160   -0.0060   -0.0100   -0.0140   -0.0040   -0.0030
        -0.0130   -0.0160   -0.0060   -0.0090   -0.0120   -0.0020   -0.0050
        -0.0120   -0.0140   -0.0050   -0.0080   -0.0110   -0.0010   -0.0030
        -0.0160   -0.0190   -0.0080   -0.0060   -0.0080    0.0030   -0.0010
         0.0010   -0.0210   -0.0050         0   -0.0020    0.0140   -0.0090
         0.0170    0.0020    0.0070    0.0040    0.0020    0.0060   -0.0090
         0.0110    0.0120    0.0040    0.0070    0.0060   -0.0010   -0.0010
         0.0170    0.0160    0.0070    0.0100    0.0120    0.0040    0.0030
         0.0080    0.0150    0.0060    0.0040    0.0110    0.0040   -0.0020
         0.0160    0.0110    0.0060    0.0100    0.0110    0.0060    0.0010]
      #
      S= 0.2 * ALPHA
      K= floor(S)+3
      if(K <= 1)
            K= 2
      end
      if(K >=  12)
            K=  11
      end
      DA= S - K +3
      L = K + fix( 1.1*sign(DA) )
      #
      S= 0.1 * BETA
      M= floor(S)+4
      if(M <= 1)
            M= 2
      end
      if(M >=  7)
            M=  6
      end
      DB= S - M + 4
      N= M + fix( 1.1*sign(DB) )
      #
      K=convert(Int64, K)
      L=convert(Int64, L)
      M=convert(Int64, M)
      N=convert(Int64, N)
      T= A[K,M]
      U= A[K,N]
      V= T + abs(DA) * (A[L,M] - T)
      W= U + abs(DA) * (A[L,N] - U)
      return dndav = V + (W-V)  * abs(DB)
end