Questions tagged [sdna]
sDNA is an acronym for Spatial Design Network Analysis
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sDNA - shapefile exception Geodesics
When calculating Geodesics with a large number (300 +) of origins and destinations (specified with 0/1 weights on links) I receive the error:
`ERR: shapefile.ShapefileException: When saving both the ...
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sDNA learn - AIC
Is there a way to show the model AIC as output to sDNA learn, in addition to mean GEH and r2? Perhaps by adding a line in sdnaregutilities?
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DXF to ArcGIS Pro - scattering of lines
I am trying to import 3D CAD polylines (DXF file) into ArcGIS Pro. However some lines scatter randomly when importing, and I am unable to understand why, or how to prevent it.
In this image, the red ...
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sDNA - randomization
I am working on a pedestrian flow model for an inner city area using sDNA and link-weighted betweenness. The network is a slightly simplified road centerline map (not OSM) where most pedestrian ...
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Map matching with sDNA?
I have a series of walking traces that I need to link to a walking network. So far, the matching algorithms available as plug-ins for QGIS (Offline Map Matching, Assisted Map-Matching) have yielded ...
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Performing analysis with sDNA toolbox using ArcGIS Notebook
I am trying to perform 'arcpy.Spatial Design Network Analysis.sDNAPrepare' command using ArcGIS Notebook on ArcGIS Pro (ver. 2.7.1). However, I have failed to run the command.
What is the problem and ...
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1
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UnicodeDecodeError: 'ascii' codec can't decode byte 0xb9 in position 23: ordinal not in range(128) [closed]
I used Prepare Network but failed. The system is Windows 11, x64. I use ArcGIS 10.6, sDNA 4.0.3.
The error is:
Executing: sDNAPrepare D:\personal\aaa.mdb\roadroad
C:\Users\69580\Documents\ArcGIS\...
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1
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Very high NQPD values for very short lines (sDNA)
I noticed that whenever a network has very short lines (less than 1-2 m), the NQPD value calculated by sDNA tends to be very high. Very short lines are often network errors, but this effect can also ...
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sDNA - sum of traffic along shortest path
I am trying to get a measure or proxy of the estimated aadt encountered along the shortest path. One way would be to compute shortest paths between origins (around 280) and destinations (one) via skim ...
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Problem with sDNA plugin setup in QGIS
When I open QGIS, a label appears:
Please ensure sDNA version 3.0 or later is installed ensure the sDNA installation folder is set correctly inProcessing -> Options -> Providers -> Spatial ...
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sDNA - OD assignment: trip length and destination weight from network
I am trying to assign trips from one origin to several destinations in sDNA, via an O-D matrix. The aim is to find average trip lengths to these destinations based on their weight.
I have used a ...
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Angular analysis in sDNA - sensitivity to small angular changes in road segments
Space syntax analysis based on shortest angular path has a few issues due to the segregated design, with small changes in angles along a generally straight route adding to the summed angular changes ...
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After sDNA integration analysis, the integration results of radius N and 500 are consistent, and the coordinate system is WGS84 Mercator projection
After sDNA integration analysis, the integration results of radius N and 500 are consistent, and the coordinate system is WGS84 Mercator projection
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When doing the accessibility analysis, the value of Mean was very low
When I did the accessibility analysis, the value of BtA500c was very low, mostly lower than 0.05. The final mean value was also very low. Two of the short lines are high. I don't know why.
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Closeness weighted sDNA Analysis
I am doing sDNA processing.
I'm trying a set closeness/farness centrality processes, differing the origin weights. But the results are not showing numerical differences for the MAD/MED, NQPD and other ...
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63
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Modelling elevation in 3D link-network for sDNA in ArcMap
I have a 3D link network model (multiple grades/levels joined by vertical links) that I would like to analyze using sDNA. Since the topography is uneven, I would like to account for the terrain before ...
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sDNA - cycle model based on start and end elevations rather than 3d shapefile
I want to run a cycle roundtrip model in sDNA. My file is a road center line (RCL) map, containing z coordinates (start Z, end Z - image attached).
The RCL vector file is shown by GRASS GIS as 3D, but ...
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Why are the results of NetQuantPD Ang Rnc and NetQuantPD Ang R50c identical after integrated analysis in SDNA？
In the integration analysis of SDNA, the radii values are n and 50, but the NetQuantPD Ang Rnc and NetQuantPD Ang R50c values in the results are exactly the same.
Is the reason for this because the ...
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56
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How to obtain the angular based betweenness using free sDNA toolbox in ArcGIS?
I am not familiar with the sDNA toolbox. I have added the free sDNA toolbox to ArcGIS. I used sDNAintegral to analysing the centrality of the network based on angular. A sample of attribute table of ...
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sDNA Installation - Unable to load DLL 'sdna_vs2008.dll'
Failed to install with the following shown on error box of "sDNA License Manager"? What can I do?
See the end of this message for details on invoking
just-in-time (JIT) debugging instead of ...
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Use and difference of "Routing and Analysis metric" and "Radial metric" in SDNA Integral Network
I want to know what it means to select Euclidean Metrics and Angular Metrics in SDNA Integral Network between "Routing and Analysis Metrics" and "Radial Metrics ".
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Why did sDNA prepare report an error
I used sDNA Prepare to repair the road network in ArcGIS10.2, but the error was always reported. Could you tell me the reason?
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Using sDNA to analyze the network downloaded from OSM, do we need to merge the network first？
In the road network downloaded from OSM, each road is divided into small sections. I would like to know whether I need to merge the sections of the road network of the same road into a complete road ...
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Predicting cycle flows assuming no traffic?
I'm trying to gauge the impact traffic has on levels of cycling. I have created a vehicle model which was used in creating a cycle model using cycle_roundtrip as the analysis. Following this, I have ...
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sDNA: tolerance problem
I used "Prepare Network" function before conducting "Integral Analysis". However, the analysis still failed because of the tolerance problem. What's wrong?
The error message:
sDNA ...
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sDNA file error
I still failed to run sDNA on my computer. I tried to do the same thing with another computer and it succeeded. I believe there is a problem with my computer. Here is the error message popped up after ...
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Non-ascii characters [duplicate]
I have posted a question about the use of sDNA in ArcGIS. It is said the problem is caused by non-ascii characters. I tired to modify the shapefile and kept the Object ID and Shape length only. ...
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Performing centrality analysis with sDNA using ArcGIS Pro
I am trying to perform centrality analysis with sDNA with ArcGIS Pro (ver. 2.7.1). However, I have failed to run the Preparation & Integral Analysis in sDNA with the same reason.
What is the ...
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2
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Inquiry of using sDNA in analysis of park accessibility in an island and its accuracy
I have a question whether sDNA closeness analysis could be used in any region/ city. I am working on an analysis of the accessibility of parks in Manhattan. You know, Manhattan is a narrow linear ...
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Performing SDNA 3d network analysis with ArcScene
I am trying to use SDNA commands to run the 3d network analysis on the ArcScene Shape file. I can view the shape file as 3d, however when I run the SDNA Prepare command, the below error message comes.
...
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hybrid metric isochrones in sDNA
I would like to use a hybrid metric to draw isochrones in sDNA. what are the possible ways, and are there any difference in the results?
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I can't use the sDNA toolbox on ArcGIS
When I import the sDNA toolbox into ArcGIS 10.2, some tools can be used, but other tools can't be used, the question are showed as follow:
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Can't find sDNA plugin with QGIS [closed]
I assume I am making a very rookie mistake here, but I can't find an sDNA plugin in QGIS. I installed and authorised the software according to the instructions. I also checked "show also ...
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Convert sDNA values to urban block
I want to join the results of sDNA analysis to urban blocks and I have a list of questions
1- Do I need to weight sDNA values of the street segments (i.e. the links) before spatial join to urban ...
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sDNA preparation network preparation fails
sDNA always fails when I run prepare network or integral analysis with a bit larger network system. I have to keep the model very small to complete process successfully.
How could I solve this?
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XY Tolerance settings of sDNA
As I ran several tools of sDNA I noticed these lines in every error report:
ERROR: Unable to obtain XYTolerance for near miss connection check
ERROR: Either add a spatial reference to the feature ...
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Loading sDNA toolbox in ArcGIS 10.6
As I loaded sDNA as a plug-in in ArcGIS 10.6 following the instructions, I found most of the tools invalid as the screencut shows. And the tools that seem loaded normally, like the network preparation ...
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Querying geodesics (shortest paths) using sDNA
I am querying geodesics with sDNA 4.0.2.
Is there a way to output a set of geodesics based on specified origin-destination pairs (specified with polyline/link IDs)?
Right now when I use the "...
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224
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Error message using sDNA Prepare Network
I'm preparing a road network using the sDNA Prepare Network tool on QGIS 2.18.28. My OS is Windows 10 64 bit.
I get the following error message:
Algorithm Prepare Network starting...
****************...
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Why sDNA error is out of memory? Can it run in 64-bit?
I use sDNA to prepare road network, but as in the pic, the error is out of memory, what can I do with it? And I notice that sDNA is running in 32-bit mode, can it run in 64-bit?
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Connectivity rule regarding two-level intersections
in the sDNA documentation here: https://www.cardiff.ac.uk/sdna/wp-content/downloads/documentation/manual/sDNA_manual_v4_0_1/network_preparation.html
is written that the network needs to be in shape as ...
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Curved lines turn to straight lines after sDNA preparation
I am an architect, sometimes I need to use sDNA to analyze networks mapped in AutoCAD. But I met a problem with curved lines, i.e. circle, or polylines.
After importing .dwg file into .gdb, and using ...
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Error message when running sDNA license manager, Windows 10 [closed]
I want to install sDNA for QGIS (Windows 10, QGIS 3) and when I try to run the license manager, I get this error message (I'm running both as admin)
I've tried to click continue, but after I copy and ...
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sDNA License Manager says Please wait?
I installed sDNA and got my license, now I'm trying to runthe sDNA License Manager. I entered the code in the field to get the Challenge URL but the status information still says:
Please wait...
I'...
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158
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Accessibility calculation with sDNA
We would like to use sDNA to calculate accessibility measures, in addition to the other measures sDNA outputs.
I've been going over the documentation a fair bit, but cannot find whether one of the ...
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Network Quantity Penalized of Distance in sDNA
I'm following up on a question asked on the calculation of the Network Quantity Penalized of Distance (NQPD) with sDNA.
I can calculate the value for the link asked in Why my calculated NQPD value ...
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43
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Usage of custom metric in hybrid analysis in sDNA
I would like to use a custom metric for the distance analysis in sDNA.
To this end, I use the following settings:
Routing and analysis metric: 'Hybrid'
Radii: same order of magnitude as the metric
...
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Speeding up sDNA analysis [closed]
I am trying to analyze several cities around the world (including major cities like London, Tokyo or Beijing) using different centrality measures with varying radiis.
The problem with this is that ...
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Using sDNA python interface [closed]
I am trying to perform road network analysis with sDNA. I have successfully generated a shapefile with all centrality measures I need using the following command in the python shell
C:\Python27\...
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2
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346
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Normalized ancular choice (NaCH) in sDNA
Based on previous experience with depthmap, I would like to inquire about a question: does sDNA has the equivalent value of NaCH (Normalized Angular Choice) or Total Depth?
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