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I have two shapefile layers showing the position of point features at two times. I would like to draw arrows showing the direction of travel of each feature (i.e. the arrows point from their position in layer 1 to their position in layer 2). I was able to do this several years ago in QGIS but I have forgotten how and I can't figure it out. I would preferably like to do it in QGIS again (I am using version 3.12), but open to using ArcGIS Pro as well.

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    Do they share an id? Or how are they linked?
    – MrXsquared
    Commented Aug 19, 2022 at 20:05
  • Welcome to GIS SE. As a new user, please take the Tour, which emphasizes the importance of asking One question per Question. Please Edit this to remove the second platform (Pro) that makes it two questions.
    – Vince
    Commented Aug 20, 2022 at 20:46

1 Answer 1

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The points in the two layers that should be connected must share an attribute with a common value, e.g. an id. Then use QGIS expressions with Geoemtry generator or Geometry by expression (see here for differences) with the following expression and style the line as arrow.

In my case, I have a layer earlier (with the field containing common attributes called attribute_name_earlier) and one later (attribute_name_later). I run the expression an the layer earlier. Change the values in the expression to match your layer and attribute-field names:

make_line (
    $geometry,
    geometry (
        get_feature(
            'later',  -- change the name to match your layer name
            'attribute_name_later',  -- change the name of the attribute
            "attribute_name_earlier"  -- change the name of the attribute
        )
    )
)

enter image description here

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  • This worked! Thank you.
    – EllieP
    Commented Aug 22, 2022 at 18:33

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