Checks the shape of an ensemble, and only the shape. It verifies the class, that `$data` is a data.table and `$draws` a list, that `$data` has the `time_series_id` and `time_series_internal_id` columns, and that every entry of `$draws` is a matrix with one row per row of `$data`.
What it does NOT check
The constructor [csfmt_ensemble_v3] establishes more than this function verifies. It does NOT check the sort order or the key. It also does NOT check:
that `time_series_internal_id` is a dense 1..n within each series;
that `time_series_label` is present;
that a draw matrix's rows still correspond to the same weeks as `$data`.
Only the row COUNT is compared, so permuting the rows of `$data` or of a draw matrix passes.
So this is not a safety net for hand-edited objects. If you have edited `$data` or `$draws` yourself, rebuild with [csfmt_ensemble_v3] rather than relying on this check.
See also
Neither package vignette covers this function. [csfmt_ensemble_v3] and every ensemble stage call it on the way out, so you rarely call it yourself.
Other ensemble format functions:
csfmt_ensemble_v3(),
print.csfmt_ensemble_v3(),
set_time_series_id()
Examples
d <- data.table::data.table(
location_code = "nation",
age = "total",
isoyearweek = c("2023-01", "2023-02", "2023-03")
)
ens <- csfmt_ensemble_v3(
d,
id_cols = c("location_code", "age"),
draws = list(numerator_nowcasted = matrix(1:12, nrow = 3))
)
# returns invisibly when the shape checks pass
validate_ensemble(ens)
# a draw matrix with the wrong number of rows is caught
bad <- ens
bad$draws$numerator_nowcasted <- matrix(1, nrow = 2, ncol = 4)
try(validate_ensemble(bad))
#> Error in validate_ensemble(bad) :
#> draws[['numerator_nowcasted']] has 2 rows; expected 3 (nrow($data))
# but a draw matrix whose rows have been PERMUTED has the right count, so it
# passes -- the row-to-week correspondence is not checked
scrambled <- ens
scrambled$draws$numerator_nowcasted <-
ens$draws$numerator_nowcasted[c(2, 3, 1), , drop = FALSE]
validate_ensemble(scrambled)
"passed, although the draws no longer line up with $data"
#> [1] "passed, although the draws no longer line up with $data"