Dataset: update the number of subjects easily

[luyckxn]

There is no easy way to update the number of subjects in the dataset.

Add a new function updateSubjects(newValue, armId=0 (default)) ?

A current workaround is to write: dataset@arms@list[[1]]@subjects <- 1

[luyckxn]

After some reflexion, I'm not really in favour to implement custom methods to modify a specific slot in a S4 object.

1) One generic way to modify a slot in a S4 object (which is used many times in the examples) is to do as follows:

# Retrieve the first arm from the dataset (or anything else)
arm <- dataset@arms %>% getByIndex(1)
# Modify a slot
arm@subjects <- as.integer(<NEW_NUMBER>)
# Replace old arm in dataset
dataset <- dataset %>% replace(arm)

2) Proposed workaround in ticket is fine as well:

dataset@arms@list[[1]]@subjects <- as.integer(<NEW_NUMBER>)

3) Create custom and parameterized functions in your simulation script:

createArm <- function(subjects) {
  arm <- Arm(subjects=subjects)
  return(arm)
}