Some new convenience features:

• sDNA Prepare now has 'dissolve' functionality when fixing split links. If you pass field names to the "merge_if_identical" keyword, then split links will only be fixed when these fields are identical.
• sDNA Integral can now preserve user-specified field data through the calculation (saving the trouble of joining output data back to the input) using the data_to_keep keyword

Some minor changes in behaviour:

• Specific Origin Accessibility Map now reports absolute diversion per destination (Div) not diversion ratio (DivR)
• sDNA Prepare when preserving non-matching text data, now concatenates strings with ";" rather than deleting them

Bug fixes

• Fixed issue where floats were sometimes read as integers

Adds compatibility with ArcGIS Professional
Adds compatibility with QGIS 3 (requires sDNA QGIS 3 Plugin to link).
Diversion ratio and Absolute Diversion now added to individual links in destination maps
Better detection of null input values
Improved sDNA Learn's cross-validated r2 calculation for single_best_variable mode. Previously, a mean r2 was taken which discarded absolute errors in prediction. Now we take a mean absolute error first then calculate r2 from it.
Fix bug which caused sDNA Learn to fail on some installations (missing optparse library)

Fixed bug in computing GEH statistic.

Fixed bug where Autocad import from link/unlink format wasn't working
Fixed bug where origin self-betweenness (etc) showed up for links not included in an intermediate link filter

This is the initial commit for sDNA Open, which branched off from the closed source sDNA at version 4.0.1.