<div dir="rtl"><div dir="ltr">Hi Markus,<br><br>I was very surprised to read your comment about v.net.distance since the manual indicates the following: <br></div><blockquote dir="ltr" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex" class="gmail_quote">
"v.net.distance - Computes shortest distance via the network between the given sets of features.<br>Finds
the shortest paths from each 'from' point to the nearest 'to' feature
and various information about this relation are uploaded to the
attribute table"<br>
</blockquote><div dir="ltr"><br>Is it possible that you had a mistake, or is it that the manual is incorrect?<br>Is the manual <b>is</b>
correct? How can I assign costs to the destination nodes to receive the
"lowest cost" (shortest) path from each origin node to the nearest
(cheapest) target node?<br>
<br><br>Best,<br><br>Dor</div><div dir="ltr" style="text-align:left" class="yj6qo ajU"><div id=":3a" class="ajR" tabindex="0"><img class="ajT" src="https://mail.google.com/mail/u/0/images/cleardot.gif"></div></div><div dir="ltr">
<br><br></div><div dir="ltr" class="gmail_quote"><div>2013/3/29 Markus Metz <span dir="ltr"><<a href="mailto:markus.metz.giswork@gmail.com" target="_blank">markus.metz.giswork@gmail.com</a>></span></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div class="im">On Thu, Mar 28, 2013 at 2:52 PM, דור פרידמן <<a href="mailto:dof1985@gmail.com">dof1985@gmail.com</a>> wrote:<br>
> Hello all,<br>
><br>
> After I've got my v.net.distance up and running I have to adjust my analysis<br>
> method to the software's capabilities. Basically, I have a 3 layered<br>
> network: myroads_net2 which contain layers as follow:<br>
><br>
> Layer 1: Arch (roads)<br>
> Layer 2: Points (Landfills - destinations)<br>
> Layer 3: Points (Settlements - source)<br>
><br>
> As one might understood I'm trying to calculate the lowest cost route<br>
> between each settlement (layer 3) to each landfill (layer 2).<br>
<br>
</div>I think v.net.distance is the wrong module for this task because it<br>
finds for each 'from' feature the nearest 'to' feature and not the<br>
shortest path from each 'from' feature to each 'to' feature. Actually,<br>
I don't think any of the v.net.* modules does exactly that. You could<br>
file a ticket for enhancement to request such a module.<br>
<div class="im"><br>
> Roads' costs<br>
> are constant, which now set to 1 (currency per distance unit - I guess that<br>
> it is meter). I would like to include a cost for landfill (gate fee) which<br>
> will be measured with the same currency. MY attempt to use ncolumn (cost for<br>
> nodes) didn't go well. I have opened a new column (double precision) in<br>
> layer 2 and named it gatefee. I have assigned 0 to all cats, except cat=3<br>
> which I have assigned with 60. My expectation was that at least some of the<br>
> settlements that were allocated to cat=3 on layer 2 will be allocated to<br>
> another one. However after running v.net.distance again with ncolumn=gatefee<br>
> I have found out that more settlements were allocated to cat=3 of layer 2.<br>
<br>
</div>If I understand the code of v.net.distance correctly, node costs are ignored.<br>
<br>
Markus M<br>
<div class="im"><br>
><br>
> Did I misused that option? I can't find any guide to how to use it in the<br>
> manual or tutorials and will appreciate an explanation or a reference to<br>
> such guide or tutorial.<br>
><br>
> Best,<br>
><br>
> Dor<br>
><br>
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</blockquote></div><div dir="ltr"><br></div></div>