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A nowcast produced by run_nowcast()

tbl_nowcast.Rd

[Experimental]

An S7 object holding a nowcast in a package-agnostic shape. It is what run_nowcast() returns and what nowcast_ensemble() and score_nowcast() consume.

Usage

tbl_nowcast(
  predictions = dplyr::tibble(),
  draws = NULL,
  method = NA_character_,
  fit = NULL,
  now = NULL,
  event_date = "event_date",
  strata = character(0),
  data = NULL,
  call = NULL,
  metadata = list()
)

Arguments

predictions

A tibble of quantile predictions. One row per (event date, stratum, quantile level) with the columns <event_date>, the strata columns, .quantile_level and .value.

draws

Either NULL (backends that only return quantiles) or a tibble with one row per (event date, stratum, draw) and the columns <event_date>, the strata columns, .draw and .value.

method

The name of the method that produced the nowcast.

fit

The untouched object returned by the backend.

now

The now of the nowcast.

event_date

Name of the event-date column in predictions/draws.

strata

Character vector with the names of the strata columns (character(0) when the nowcast is not stratified).

data

The tbl_now the nowcast was produced from.

call

The matched call of run_nowcast().

metadata

A named list with anything else the backend wants to keep.

Value

A tbl_nowcast object.

See also

run_nowcast(), nowcast_ensemble(), score_nowcast()

Examples

# Normally built for you by the one-call front door, but the constructor is
# exported because a new backend -- or a test -- needs to build one directly.
predictions <- data.frame(
  onset_week = as.Date("2020-01-05") + c(0, 0, 7, 7),
  .quantile_level = c(0.5, 0.9, 0.5, 0.9),
  .value = c(10, 14, 12, 17)
)
tbl_nowcast(predictions = predictions, method = "toy", event_date = "onset_week")
#> ── A <tbl_nowcast> from method "toy" ───────────────────────────────────────────
#> • now: 
#> • event dates: 2
#> • quantile levels: 0.5 and 0.9
#> • draws: none (quantiles only)
#> 
#> Nowcast at "2020-01-12" (q50):
#> • 12
#> 
#> # A tibble: 4 × 3
#>   onset_week .quantile_level .value
#>   <date>               <dbl>  <dbl>
#> 1 2020-01-05             0.5     10
#> 2 2020-01-05             0.9     14
#> 3 2020-01-12             0.5     12
#> 4 2020-01-12             0.9     17