Fix trt assign

[kgoldfeld]

@assignUser I created this new pull request. Not sure this is proper workflow, but it is what it is. Check it out. It seems to do the trick.

[assignUser]

Yep totally fine to open another PR for the same thing! Looks fine to me. Though this leaves trtObserve to produce 0/1 for singular formulas and 1...n for n formulas but I guess that makes sense withing the context of that function and is also mentioned in the docs:

@return An integer (group) ranging from 1 to length of the probability vector

[github-actions]

This is how benchmark results would change (along with a 95% confidence interval in relative change) if 8144616 is merged into main:

•   :ballot_box_with_check:define_data: 21.8ms -> 21.8ms [-0.25%, +0.6%]
•   :ballot_box_with_check:dist_beta: 279ms -> 280ms [-0.64%, +1.23%]
•   :ballot_box_with_check:dist_binary: 16ms -> 16ms [-0.93%, +0.69%]
•   :ballot_box_with_check:dist_binomial: 19.6ms -> 19.6ms [-0.84%, +0.93%]
•   :ballot_box_with_check:dist_categorical: 92.8ms -> 92.2ms [-2.34%, +1.04%]
•   :ballot_box_with_check:dist_exponential: 14.7ms -> 14.7ms [-0.54%, +0.83%]
•   :ballot_box_with_check:dist_gamma: 27ms -> 26.9ms [-1.04%, +0.88%]
•   :ballot_box_with_check:dist_mixture: 302ms -> 303ms [-1.1%, +2.12%]
•   :ballot_box_with_check:dist_normal: 19ms -> 19.1ms [-0.31%, +0.94%]
•   :ballot_box_with_check:gen_all_dists: 71.5ms -> 71.5ms [-0.4%, +0.38%]
  Further explanation regarding interpretation and methodology can be found in the documentation.

[github-actions]

This is how benchmark results would change (along with a 95% confidence interval in relative change) if 73de6bc is merged into main:

•   :ballot_box_with_check:define_data: 24.4ms -> 24.3ms [-3.57%, +2.43%]
• ❗🐌dist_beta: 318ms -> 323ms [+0.08%, +3.42%]
•   :ballot_box_with_check:dist_binary: 17.9ms -> 18.2ms [-2.26%, +5.67%]
•   :ballot_box_with_check:dist_binomial: 22.9ms -> 22.6ms [-3.22%, +0.62%]
•   :ballot_box_with_check:dist_categorical: 107ms -> 108ms [-2.1%, +3.19%]
•   :ballot_box_with_check:dist_exponential: 16.7ms -> 16.9ms [-1.73%, +3.38%]
•   :ballot_box_with_check:dist_gamma: 31ms -> 30.6ms [-4.69%, +1.86%]
•   :ballot_box_with_check:dist_mixture: 348ms -> 351ms [-1.51%, +3.25%]
•   :ballot_box_with_check:dist_normal: 21.7ms -> 21.6ms [-3.48%, +2.81%]
•   :ballot_box_with_check:gen_all_dists: 81.9ms -> 79.9ms [-6.15%, +1.28%]
  Further explanation regarding interpretation and methodology can be found in the documentation.