I have an error that I cannot understand. It looks like I forgot to load a library but I've gone through all the available d3 libraries I can't see which library has reduceInitial as a function.
I use:
d3 v3.5.17
dc v2.0.5
crossfilter v1.3.14
jquery v3.6.1
d3-color v1.4.1
d3-format v1.4.5
d3-interpolate v1.4.0
d3-scale v2.2.2
d3-scale.chromatic v1.5.0
d3-time v1.1.0
d3 v2.3.0
Many thanks in advance for your help
This is the third parameter to group.reduce() and it expects a function.
You probably neglected to pass this parameter, so it's trying to call undefined as a function.