CODEWITHSUNDEEP
excelvbaexcel-formulageocoding
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Reputation: 13

Find Distance between different coordinates

I have Location data (latitude and longitude) of 1000's of locations and need to compute the distance between each of them taken two combinations at a time.

Example:

Let's just say I have four location data (latitude and longitude data) and want to compute the distance between them 

    Location      Latitude    Longitude

 1. New York(L1)  40.7128° N  74.0060° W
 2. Paris(L2)     48.8566° N   2.3522° E
 3. London(L3)    51.5074° N   0.1278° W
 4. Moscow(L4)    55.7558° N  37.6173° E

Need to calculate the distance between possible combinations i.e distance between L1&L2, L1&L3, L1&L4, L2&L3, L2&L4 and L3&L4

Excel Formula I'm using to compute distance is

=ACOS(COS(RADIANS(90-Lat1)) *COS(RADIANS(90-Lat2)) +SIN(RADIANS(90-Lat1)) *SIN(RADIANS(90-Lat2)) *COS(RADIANS(Long1-Long2))) *6371

How can I calculate it for large data set say 100's or 1000's of locations?

Upvotes: 1

Views: 3452

Answers (2)

Automate This
Automate This

Reputation: 31364

Alternatively, you can create a VBA function and then loop through your table.

Add this code to a Module in the VBA editor:

Public Function DistBetweenCoord(Lat1 As Double, Long1 As Double, Lat2 As Double, Long2 As Double)
    'Cell Formula
    'ACOS(COS(RADIANS(90-Lat1)) *COS(RADIANS(90-Lat2)) +SIN(RADIANS(90-Lat1)) *SIN(RADIANS(90-Lat2)) *COS(RADIANS(Long1-Long2))) *6371

    With WorksheetFunction
        A = Cos(.Radians(90 - Lat1))
        B = Cos(.Radians(90 - Lat2))
        C = Sin(.Radians(90 - Lat1))
        D = Sin(.Radians(90 - Lat2))
        E = Cos(.Radians(Long1 - Long2))

        DistBetweenCoord = .Acos(A * B + C * D * E) * 6371
    End With
End Function

Now you can access this through code or in cell. Here is an example of in-cell:

=DistBetweenCoord(C1,D1,C2,D2)

Here is how to loop through all possible combinations in another Sub. Output is in immediate window.

Sub CalcAllDistances()
    With Worksheets("Sheet1")
        For i = 1 To 4
            For j = i To 4
                If i <> j Then
                    Debug.Print .Cells(i, 2) & " to " & .Cells(j, 2) & ": " & DistBetweenCoord(.Cells(i, 3), .Cells(i, 4), .Cells(j, 3), .Cells(j, 4))
                End If
            Next j
        Next i
    End With
End Sub

enter image description here

EDIT - To change output to Sheet2 try the following:

Sub CalcAllDistances()
    Dim wks_Output As Worksheet
    Set wks_Output = Worksheets("Sheet2")

    Dim OutputRow As Long: OutputRow = 1

    With Worksheets("Sheet1")
        For i = 1 To 4
            For j = i To 4
                If i <> j Then
                    wks_Output.Cells(OutputRow, 1).Value = .Cells(i, 2) & " to " & .Cells(j, 2)
                    wks_Output.Cells(OutputRow, 2).Value = DistBetweenCoord(.Cells(i, 3), .Cells(i, 4), .Cells(j, 3), .Cells(j, 4))
                    OutputRow = OutputRow + 1
                End If
            Next j
        Next i
    End With
End Sub

enter image description here

Upvotes: 3

MarkO
MarkO

Reputation: 113

I would use a matrix. Create a sheet (like 'GeocodeList' or something) for the geocodes, like your city|lat|lon in the question. Then create a sheet (like 'Distances') for a matrix, where the column and row labels are the city names. Then you can parameter your excel formula using V.LOOKUPs that look up exact codes from GeocodeList.

The formula would look like this (X is row number, Y is column letter.):

=ACOS(COS(RADIANS(90-VLOOKUP($A(X); GEOCODETABLE, LATCOLINDEX, 0)))
*COS(RADIANS(90-VLOOKUP((Y)$1; GEOCODETABLE; LATCOLINDEX, 0)))
+SIN(RADIANS(90-VLOOKUP($A(X); GEOCODETABLE, LATCOLINDEX, 0)))
*SIN(RADIANS(90-VLOOKUP((Y)$1; GEOCODETABLE; LATCOLINDEX, 0)))
*COS(RADIANS(VLOOKUP($A(X); GEOCODETABLE, LATCOLINDEX, 0)-VLOOKUP((Y)$1; GEOCODETABLE; LONCOLINDEX, 0))))
*6371

So basically the VLOOKUP automatically fetches your parameters, and you can extend the formula for the whole matrix.

Upvotes: 2

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