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  • 1.  how many line intersect at particular point on map

    Employee
    Posted 12-30-2022 03:48
    I have a requirement where i need to identify how many line intersect at particular point on map.
    lines & point of intersection are already map by me on mapinfo.

    Regards,
    Yogesh



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    yogesh pawar
    Precisely Software Inc.
    Pune
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  • 2.  RE: how many line intersect at particular point on map

    Employee
    Posted 01-02-2023 03:49
    Hi Yogesh

    You can run a query to get the result if you want to find all lines that pass through a given point.

    I'd choose a sub-select for this specific purpose but you can also use a spatial join if you prefer. Here's a sub-select Select statement that will do what you are after:
    Select *
    From Roads
    Where OBJ Intersects
       (Select AggregateCombine(obj) From Accidents)
    Into Selection

    Below you can see the result of the query shown as purple lines

    You can also use Select by Location to find the lines that intersect. This is quite simple as you don't need to write any SQL.

    If you need to apply some tolerance to the query, you can do this too. With Select by Location, you can use the operator Within a Distance and specify the distance between the point and lines that you will allow.

    In my example, I have set a distance of 20 meters. The distance can be as short or long as you like.

    You can also do this through a sub-select using the AggregateBuffer where you create a buffer around your point(s) and use this to search for intersecting lines:
    Select *
    From Roads
    Where OBJ Intersects
       (Select AggregateBuffer(obj, 36, 20, "m")
          From Accidents)
    Into Selection

    I hope this helps

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    Peter Horsbøll Møller
    Principal Presales Consultant | Distinguished Engineer
    Precisely | Trust in Data
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