I have a road network (vector) that i'm interested in carrying out some space syntax analysis on.
Predictably my GIS data is in a pretty terrible state. For example, there are a bunch of roads on the network that look like they join but do not. I've managed to fix some of this (on the surface at least) with the GRASS v.clean tool in QGIS.
My big problem though is polylines. In nearly every case I have long stretches of road that are stored as separate polylines. For example, a long trunk road, split into 5 or 6 separate lines even if they have all snapped together. Worse still in some cases these sections have been given different (or slightly different) road names and have no common identifying attribute.
I was really hoping that there would be a (fairly) simple method of simplifying this network to allow me to run the space syntax analysis tools to actually give a meaningful output. I've read around a lot of forums and played with a few plugins in QGIS (Network plugin; Roadgraph plugin) without much joy. I have been reading a previous post on automating the cleaning process but this doesn't get me very far either.
I'm just wondering if anyone has come across a simple tutorial on how I might achieve this - or whether you think its worth bothering. I have had an offer from someone to re-draw the entire network as an alternative!
Any hints/tips/experiences welcome!
cheers
Marty
p.s. using QGIS 2.10 on Ubuntu 14.04 - but open to suggestions of other software/solutions: R; Python etc..
أكثر...
Predictably my GIS data is in a pretty terrible state. For example, there are a bunch of roads on the network that look like they join but do not. I've managed to fix some of this (on the surface at least) with the GRASS v.clean tool in QGIS.
My big problem though is polylines. In nearly every case I have long stretches of road that are stored as separate polylines. For example, a long trunk road, split into 5 or 6 separate lines even if they have all snapped together. Worse still in some cases these sections have been given different (or slightly different) road names and have no common identifying attribute.
I was really hoping that there would be a (fairly) simple method of simplifying this network to allow me to run the space syntax analysis tools to actually give a meaningful output. I've read around a lot of forums and played with a few plugins in QGIS (Network plugin; Roadgraph plugin) without much joy. I have been reading a previous post on automating the cleaning process but this doesn't get me very far either.
I'm just wondering if anyone has come across a simple tutorial on how I might achieve this - or whether you think its worth bothering. I have had an offer from someone to re-draw the entire network as an alternative!
Any hints/tips/experiences welcome!
cheers
Marty
p.s. using QGIS 2.10 on Ubuntu 14.04 - but open to suggestions of other software/solutions: R; Python etc..
أكثر...