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I am interested in building a raster of the distance from rivers in a territory under study. I have digitized the course of the rivers in ArcGis 10.1. I have used the 'Euclidean Distance' tool to create a raster of the distance from rivers. Now, since we are moving in a 3D world, not in a 2D one, I would like to 'weight' the calculated distances in order to take the elevation into account.

So, I would like to know how can I create a raster depicting the distance of any point from rivers, also taking into account the elevation variable.

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  • Maybe the additional distance from elevation change could be added in as a cost raster, then you'd need to sum the cost along a straight line distance for a given point and add that value to the regular Euclidean distance?
    – Erica
    Jul 13, 2014 at 22:20
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    Are you trying to determine the flow distance to the nearest river based on flow direction? Or the straight-line distance that accounts for slope?
    – dmahr
    Jul 14, 2014 at 0:44
  • @dmarh: I would like to use the distance-to-river raster as one of the independent variables of a Logistic regression model
    – NewAtGis
    Jul 14, 2014 at 9:30
  • @Erica: I do not follow you. My bad :-(
    – NewAtGis
    Jul 14, 2014 at 9:30

1 Answer 1

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if you need more advanced distance calculation, you should use the Path distance instead of the Euclidian distance. This allow you to account for the slope in the direction of the movement, which is necessary to adapt the true distance with respect to the elevation (using an elevation change as a cost raster does not work because this elevation change is only valid in one out of 8 directions).

You do not have to use all feature, but you can define a vertical raster and a vertical factor (see here for the details)

EDIT: if you need to compute "best" path from A to B, you can use cost path with the result of the path distance (including the optional backlink raster) instead of Euclidian cost and direction rasters. Note that contrary to euclidian distance, best path from A to B might not be the same as "best" path from B to A.

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  • Thanks. Sorry for the question which can seem very basic, but my main concern is: does 'path distance' take into account two points (start and ending point)?
    – NewAtGis
    Jul 14, 2014 at 9:44
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    it is the same as costdistance but with other criteria added. The help file link resources.arcgis.com/en/help/main/10.2/index.html#/… is quite useful in this regard
    – user681
    Jul 14, 2014 at 10:01

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