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gremlinamazon-neptune

Gremlin property math on a single vertex

I'm trying to perform some math on the properties of a Vertex. My solution works in the Gremlin console, but throws an error when run in JavaScript.

gremlin> g.addV("trip").property(single, "trackLength", 100).property(single, "travelDistance", 75).property(single, "carWeight", 10)

==>v[f8b42b9d-9053-2838-808d-ba14606b8390]

gremlin> g.V("f8b42b9d-9053-2838-808d-ba14606b8390").property(single, "carFactor", __.project("trackLength", "travelDistance", "carWeight").by("trackLength").by("travelDistance").by("carWeight").math("(trackLength - travelDistance) * carWeight")).valueMap()

I get the expected result when running in the console:

==>{trackLength=[100], travelDistance=[75], carWeight=[10], carFactor=[250.0]}

However when I run this in JS I get an error:

TypeError: __.project(...).by(...).by(...).by(...).math is not a function

Gremlin version 3.2.10. I've tried upgrading to ^3.4.0 but am encountering a separate issue addressed here.

Solution

  • The math() step was only introduced on 3.3.1, so if you're using 3.2.10, that's not going to work. Perhaps try 3.3.5 and see if math() works there.