# Expandify implementation notes

#### Irena Papst

A place to keep notes on expandify implementation (ageify, vaxify) assumptions and future work (instead of relying on disparate FIXMEs).

## Assumptions

### General

`distribute_counts()`

(via `smart_round()`

: preferentially fills counts from right to left (e.g. in `expand_state_age`

, counts from a specified state will be distributed from older age groups to younger)

### Vaxify

`expand_state_vax()`

: everyone starts in the unvaccinated compartment, regardless of epi status or point in the epidemic.
- Can we actually already get around this by specifying
`make_state(x = vec)`

?

`mk_vaxrates()`

: we need to know (or be able to calculate the number of doses per day administered to each subgroup (e.g. age category) of the population.

## To fix/do

`condense_vax()`

: make it work for ageified case (don’t condense over age groups)
`mk_vaxrates()`

: check that it works for ageified parameters (specifically the `doses_per_day/params[["N"]]`

calculation, since this is a vector divided by a vector)

## Questions (for Ben)

- I have a choice between handling the calculation of per capita daily vaccination rates as a pre-processing step or in the sim… does it matter for
`timepars`

or `calibrate`

when these rates are calculated?