Usage of custom metric in hybrid analysis in sdna

Question

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 
Radial metric: Custom or Hybrid (see below)
Custom metric field: Empty
Advanced config: lineformula = euc/FULLeuc*column_name

If I set the radial metric to hybrid, I receive the error message: 'ERROR: Error in formula for link metric'.

If I set the radial metric to custom, there is no change in the output values (e.g. betweenness remains the same, I assume because the same links are considered in the calculation).

The purpose of the custom metric is to reward/penalize more/less attractive links in the calculation of metrics.

My example network can be found here.

Software:
ArcGIS 10.5.1
sDNA+ 3.4.5

Sideshow Bob · Answer

Michael is correct in his comment; for hybrid radial metrics then radlineformula and radjuncformula must be set in advanced config. For hybrid analytical metrics the equivalents are lineformula and juncformula. This allows use of different metrics for the radius and routing/analysis which is useful more often than you'd think, to make results more interpretable - see this paper.

Alternatively set the radial metric to MATCH_ANALYTICAL and then you only need to set lineformula and juncformula.

Custom metrics are something altogether simpler, they read a single data field off each link rather than an expression. You need to provide the appropriate field name in the configuration dialog; if not then it assumes all links have the same metric (=1) which gives you topological analysis.

Usage of custom metric in hybrid analysis in sdna

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