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SCHAPELM's avatar
SCHAPELM
New Member
3 years ago
Solved

Calculation distance between latitudes & Longitudes

I currently want to calculate the distance between two sites based on the lattitude & longitude. The lattitude & longitude are currently contained within the table listed against each site.

 

How i want it to work

 

Step 1: Select Site 1

Step 2:Select Site 2

= Result Distance between site 1 & 2

 

 

I need help in creating the two measures required for step 1 & step 2 then writing the equasion for the result.

 

I know the calculation to to work out the distance is:
 =acos(sin(lat1)*sin(lat2)+cos(lat1)*cos(lat2)*cos(lon2-lon1))*6371


Im new to power BI but fluent in tableau so i know how it should work in that format but new to DAX

 

Thanks 
Matt

  • tamerj1's avatar
    tamerj1
    3 years ago

    SCHAPELM 
    Thank you.

    Please refer to attached sample file with the proposed solution

    Distance = 
VAR FromSite = SELECTEDVALUE ( 'Site From'[From Site] )
VAR FromTable = FILTER ( 'Table', 'Table'[SiteDescription] = FromSite )
VAR FromLatitude = MAXX ( FromTable, 'Table'[Latitude] )
VAR FromLongitude = MAXX ( FromTable, 'Table'[Longitude] )
VAR ToSite = SELECTEDVALUE ( 'Site To'[To Site] )
VAR ToTable = FILTER ( 'Table', 'Table'[SiteDescription] = ToSite )
VAR ToLatitude = RADIANS ( MAXX ( ToTable, 'Table'[Latitude] ) )
VAR ToLongitude = RADIANS ( MAXX ( ToTable, 'Table'[Longitude] ) )
RETURN 
    ACOS ( 
        SIN ( FromLatitude ) * SIN ( ToLatitude ) 
            + COS ( FromLatitude ) * COS ( ToLatitude ) * COS ( ToLongitude - FromLongitude ) 
    ) * 6371

6 Replies

  • tamerj1's avatar
    tamerj1
    Icon for Community Champion rankCommunity Champion
    3 years ago

    Hi SCHAPELM 
    How do you have the locations in your data?
    Do you have the latitude and longitude in separate columns or together in one column? please present a sample

  • SCHAPELM's avatar
    SCHAPELM
    New Member
    3 years ago

    Hi tamerj1 
    the latitude and longitude are in seperate columns within the table against each site

    below is an example of how it is presented

     

    SiteDescriptionLatitudeLongitude
    Site 1-49.22121.86
    Site 2-38.04140.67
    Site 3-38.00140.71
    Site 4-37.94140.73
    Site 5-37.9140.56
    • tamerj1's avatar
      tamerj1
      Icon for Community Champion rankCommunity Champion
      3 years ago

      SCHAPELM 
      Thank you.

      Please refer to attached sample file with the proposed solution

      Distance = 
VAR FromSite = SELECTEDVALUE ( 'Site From'[From Site] )
VAR FromTable = FILTER ( 'Table', 'Table'[SiteDescription] = FromSite )
VAR FromLatitude = MAXX ( FromTable, 'Table'[Latitude] )
VAR FromLongitude = MAXX ( FromTable, 'Table'[Longitude] )
VAR ToSite = SELECTEDVALUE ( 'Site To'[To Site] )
VAR ToTable = FILTER ( 'Table', 'Table'[SiteDescription] = ToSite )
VAR ToLatitude = RADIANS ( MAXX ( ToTable, 'Table'[Latitude] ) )
VAR ToLongitude = RADIANS ( MAXX ( ToTable, 'Table'[Longitude] ) )
RETURN 
    ACOS ( 
        SIN ( FromLatitude ) * SIN ( ToLatitude ) 
            + COS ( FromLatitude ) * COS ( ToLatitude ) * COS ( ToLongitude - FromLongitude ) 
    ) * 6371
  • SCHAPELM's avatar
    SCHAPELM
    New Member
    3 years ago

    Hi tamerj1 
    Thankyou for this,
    just curious as I have plotted all my sites on a map (over 500) is it possible to use the map to autoselect  'Site 1' & 'Site 2' fields in the equasion
    In essence you select site 1 from the map, then select site 2 and a card displayed on the report would show the distance. Understand if this is too complex

    cheers

    • tamerj1's avatar
      tamerj1
      Icon for Community Champion rankCommunity Champion
      3 years ago

      SCHAPELM 
      Please see attached modified sample file

      Distance = 
IF ( 
    COUNTROWS ( VALUES ( 'Table'[SiteDescription] ) ) = 2,
    VAR FromTable = TOPN ( 1, 'Table', 'Table'[SiteDescription], ASC )
    VAR Lat1 = RADIANS ( MAXX ( FromTable, 'Table'[Latitude] ) )
    VAR Lon1 = RADIANS ( MAXX ( FromTable, 'Table'[Longitude] ) )
    VAR ToTable = TOPN ( 1, 'Table', 'Table'[SiteDescription] )
    VAR Lat2 = RADIANS ( MAXX ( ToTable, 'Table'[Latitude] ) )
    VAR Lon2 = RADIANS ( MAXX ( ToTable, 'Table'[Longitude] ) )
    RETURN 
        ACOS ( 
            SIN ( Lat1 ) * SIN ( Lat2 ) 
                + COS ( Lat1 ) * COS ( Lat2 ) * COS ( Lon2 - Lon1 ) 
        ) * 6371,
    "Select two locations"
)
  • Anonymous's avatar
    Anonymous
    Not applicable
    3 years ago

    Dear all,

     

    i replied your code on my project in order to obtain the distance in kilometers. Unfortunately, the result is not accurate. Is it a data latitud/longitud problem? I'm affraid not bcs I tested it on a website and it recognized the kilometer distance correctly.

     

    Brief:

    - on my original database i had repeated coordinates several times since each row is a zipcode;

    - I named my site1 as "origem" and remove duplicated coordinates;

    - I named my site2 as "destination" and remove duplicated coordinates;
    - "admin name3" is location name;
    - i already testing removing duplicates in original database but nothing changed;


    my measure is:

    Distance =
    VAR FromSite = SELECTEDVALUE ( Origem[admin name3] )
    VAR FromTable = FILTER ( 'Origem', 'Origem'[admin name3] = FromSite )
    VAR FromLatitude = MAXX ( FromTable, 'Origem'[Latitude] )
    VAR FromLongitude = MAXX ( FromTable, 'Origem'[Longitude] )
    VAR ToSite = SELECTEDVALUE ( Destino[admin name3] )
    VAR ToTable = FILTER ( 'Destino', 'Destino'[admin name3] = ToSite )
    VAR ToLatitude = RADIANS ( MAXX ( ToTable, 'Destino'[Latitude] ) )
    VAR ToLongitude = RADIANS ( MAXX ( ToTable, 'Destino'[Longitude] ) )
    RETURN
        ACOS (
            SIN ( FromLatitude ) * SIN ( ToLatitude )
                + COS ( FromLatitude ) * COS ( ToLatitude ) * COS ( ToLongitude - FromLongitude )
        ) * 6371


    Could someone help me? I'm not getting why kilometeres are incorrect. Is due tables relationship? i kept it without any connection as you showed on your summary.

     

    Thank you in advance