controlling the mean and sd for the first variable in an with r_series

[rpietro]

@trinker , amazing package. Quick question, can I have control over the mean and sd for the first variable in an r_series? It would probably look like this:

r_series(normal(mean = 35, sd = 10, min = 10, max = 45), 2, 100, name = "Question", relate = list(operation = "+", mean = 5, sd = 10))

[trinker]

Sounds reasonable...I'll have a look when I have dev time allotted for wakefield.