Several representations to run the same learners across

The set a learner without a data = of its own is fitted at every member of. grains() names calendar grains, lookbacks() names lookback spans, and either takes its arguments as separate names or as one vector.

Usage

grains(..., stats = "mean", year_start = "09-01")

lookbacks(..., lag = "0 days", bins = 1L, stats = "mean")

as_sift(x)

Arguments

...

Grain names for grains(), lookback spans for lookbacks(), given as separate arguments or as one vector.

stats

Statistics computed per bin, one channel each, in the order given. See grain_matrix() for the seven and for what separates an extreme reading from an extreme day.

year_start

"MM-DD" boundary of the hydrological year, used by "season" and "year".

lag

The gap between a target's instant and the end of its lookback.

bins

Sub-bins the lookback is cut into, oldest first. One gives a block of features, several give a sequence.

x

A named list of representations, a single representation, or a character vector of grain names.

Value

A timesift_sift: a named list of representations, labelled by each one's own label where the list was not named.

Details

grains("auto") is the set of named grains the record gives at least two bins, in the order native, halfday, day, week, month, season, year, leaving out any grain the requested statistics are not defined at. There is no cap on it: over three years of hourly readings native is 26304 bins, and a caller who does not want that names the grains instead.

Examples

grains("day", "week", "month")
grains(c("month", "year"), stats = c("cold_day", "mean", "warm_day"))
lookbacks("30 days", "90 days", bins = 3L)