Rob: Downplay role of R6

[amyheather]

Code Organisation

consider downplaying role of R6. Maybe overkill for users?

Originally posted by @robchallen in #152

R6 Classes

From discussion with Rob, I'm thinking potential approach may be:

• Remove mention from R6 classes from book
• Where I have used them, wrap in functions

For reference, the only place I have used R6 classes is in code for choosing the number of replications.

https://pythonhealthdatascience.github.io/des_rap_book/pages/guide/output_analysis/n_reps.html#automated

There are three R6 classes: WelfordStats, ReplicationTabuliser and ReplicationsAlgorithm.

Why are they classes? Because I was converting from Python package sim-tools which uses classes, so I just followed the same logic.

In terms of readers of the book and what they need to understand - they don't really need to understand R6 - we suggest they use functions as that's typical to R - and here, they just use them like below, but could just have a wrapper.

# Set up algorithm
alg <- ReplicationsAlgorithm$new(
  param = create_params(warm_up_period = 10000L,
                        data_collection_period = 10000L),
  metrics = metrics
)

# Run algorithm
alg$select()

# View recommended number of replications
alg$nreps

UPDATE: Do also talk about quite alot on the parameter validation page.

_Originally posted by @amyheather in #152

[amyheather]

Remaining pages to sort out:

• patients.qmd - DistributionRegistry
• n_reps.qmd - WelfordStats, ReplicationTabuliser, and ReplicationsAlgorithm