MatrixR{i,j}.bas

' Special matrix R(i, j) (https://habrahabr.ru/post/336684/)

Option Explicit
Option Base 1

'12345678901234567890123456789012345bopoh13@ya67890123456789012345678901234567890
Function getR(p() As Double, q() As Double) As Double
  Dim i As Integer, j As Integer
  Dim Rx As Double, Ry As Double, Rz As Double
  Dim R(5000, 5000) As Double, begin As Double
    
  begin = Timer
  For i = 1 To UBound(p, 1)
    For j = 1 To UBound(q, 2)
      Rx = p(i, 1) - q(1, j)
      Ry = p(i, 2) - q(2, j)
      Rz = p(i, 3) - q(3, j)
      
      R(i, j) = 1 / (1 + Sqr(Rx * Rx + Ry * Ry + Rz * Rz))
   Next j, i: getR = (Timer - begin) * 1000
End Function

Sub Time_spent_Testing() ' N = 5000
  Dim p(5000, 3) As Double, q(3, 5000) As Double, i As Integer
  
  For i = 1 To 5000
    p(i, 1) = Rnd: p(i, 2) = Rnd: p(i, 3) = Rnd
    q(1, i) = Rnd: q(2, i) = Rnd: q(3, i) = Rnd
  Next i: Debug.Print Format(getR(p, q), "0 000 мс") ' 7 453 мс
End Sub