Une des fonctions les plus communes de la géographie et des systèmes modernes, c'est le calcul de la distance géographique entre deux coordonnées de Longitude et de Latitude. Il n'y a aucune nécessité de grande connaissance en trigonométrie pour arriver à se genre de calcul dans le format qu'on le souhaite, Km, Miles ou Miles Nautiques. Ainsi, si vous savez les coordonnéss suivantes :
| Ville | Latitude | Longitude |
|---|---|---|
| Montréal | 45 31N | 73 34O |
| Paris | 48 50N | 2 20E |
A l'aide du code source LotusScript suivant, vous trouvez la réponse que vous souhaitez :
- Sub Main
- Print "Distance entre Montréal et Paris en Km: " + Str$(CoordToDeltaKm(45, 31, "N", 73, 34, "O", 48, 50, "N", 2, 20, "E"))
- Print "Distance entre Montréal et Paris en Miles: " + Str$(CoordToDeltaStatuteMiles(45, 31, "N", 73, 34, "O", 48, 50, "N", 2, 20, "E"))
- Print "Distance entre Montréal et Paris en Miles Nautique: " + Str$(CoordToDeltaNauticalMiles(45, 31, "N", 73, 34, "O", 48, 50, "N", 2, 20, "E"))
- End Sub
-
- Function CoordToDeltaKm( _
- Byval Q1Latitude As Double, Byval Q1LatiDeg As Double, Byval Q1LatiDirection As String, _
- Byval Q1Longitude As Double, Byval Q1LongDeg As Double, Byval Q1LongDirection As String, _
- Byval Q2Latitude As Double, Byval Q2LatiDeg As Double, Byval Q2LatiDirection As String, _
- Byval Q2Longitude As Double, Byval Q2LongDeg As Double, Byval Q2LongDirection As String) As Double
- Dim a1, b1, a2, b2, RawDelta As Double
- a1 = (Q1Latitude + (Q1LatiDeg / 60)) * Pi / 180
- If Q1LatiDirection = "N" Then
- a1 = -a1
- End If
- b1 = (Q1Longitude + (Q1LongDeg / 60)) * Pi / 180
- If Q1LongDirection = "O" Then
- b1 = -b1
- End If
- a2 = (Q2Latitude + (Q2LatiDeg / 60)) * Pi / 180
- If Q2LatiDirection = "N" Then
- a2 = -a2
- End If
- b2 = (Q2Longitude + (Q2LongDeg / 60)) * Pi / 180
- If Q2LongDirection = "O" Then
- b2 = -b2
- End If
- RawDelta = Acos(Cos(a1) * Cos(b1) * Cos(a2) * Cos(b2) + Cos(a1) * Sin(b1) * Cos(a2) * Sin(b2) + Sin(a1) * Sin(a2))
- CoordToDeltaKm = RawDelta * 6378.0
- End Function
-
- Function CoordToDeltaNauticalMiles( _
- Byval Q1Latitude As Double, Byval Q1LatiDeg As Double, Byval Q1LatiDirection As String, _
- Byval Q1Longitude As Double, Byval Q1LongDeg As Double, Byval Q1LongDirection As String, _
- Byval Q2Latitude As Double, Byval Q2LatiDeg As Double, Byval Q2LatiDirection As String, _
- Byval Q2Longitude As Double, Byval Q2LongDeg As Double, Byval Q2LongDirection As String) As Double
- Dim a1, b1, a2, b2, RawDelta As Double
- a1 = (Q1Latitude + (Q1LatiDeg / 60)) * Pi / 180
- If Q1LatiDirection = "N" Then
- a1 = -a1
- End If
- b1 = (Q1Longitude + (Q1LongDeg / 60)) * Pi / 180
- If Q1LongDirection = "O" Then
- b1 = -b1
- End If
- a2 = (Q2Latitude + (Q2LatiDeg / 60)) * Pi / 180
- If Q2LatiDirection = "N" Then
- a2 = -a2
- End If
- b2 = (Q2Longitude + (Q2LongDeg / 60)) * Pi / 180
- If Q2LongDirection = "O" Then
- b2 = -b2
- End If
- RawDelta = Acos(Cos(a1) * Cos(b1) * Cos(a2) * Cos(b2) + Cos(a1) * Sin(b1) * Cos(a2) * Sin(b2) + Sin(a1) * Sin(a2))
- CoordToDeltaNauticalMiles = RawDelta * 3443.9
- End Function
-
- Function CoordToDeltaStatuteMiles( _
- Byval Q1Latitude As Double, Byval Q1LatiDeg As Double, Byval Q1LatiDirection As String, _
- Byval Q1Longitude As Double, Byval Q1LongDeg As Double, Byval Q1LongDirection As String, _
- Byval Q2Latitude As Double, Byval Q2LatiDeg As Double, Byval Q2LatiDirection As String, _
- Byval Q2Longitude As Double, Byval Q2LongDeg As Double, Byval Q2LongDirection As String) As Double
- Dim a1, b1, a2, b2, RawDelta As Double
- a1 = (Q1Latitude + (Q1LatiDeg / 60)) * Pi / 180
- If Q1LatiDirection = "N" Then
- a1 = -a1
- End If
- b1 = (Q1Longitude + (Q1LongDeg / 60)) * Pi / 180
- If Q1LongDirection = "O" Then
- b1 = -b1
- End If
- a2 = (Q2Latitude + (Q2LatiDeg / 60)) * Pi / 180
- If Q2LatiDirection = "N" Then
- a2 = -a2
- End If
- b2 = (Q2Longitude + (Q2LongDeg / 60)) * Pi / 180
- If Q2LongDirection = "O" Then
- b2 = -b2
- End If
- RawDelta = Acos(Cos(a1) * Cos(b1) * Cos(a2) * Cos(b2) + Cos(a1) * Sin(b1) * Cos(a2) * Sin(b2) + Sin(a1) * Sin(a2))
- CoordToDeltaStatuteMiles = RawDelta * 3963.1
- End Function
on obtiendra le résultat suivant :
Distance entre Montréal et Paris en Km: 5510.16761889Distance entre Montréal et Paris en Miles: 3423.85470217
Distance entre Montréal et Paris en Miles Nautique: 2975.30044884
Dernière mise à jour : Dimanche, le 18 janvier 2015