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Register a weather transform for the session

Source: R/class-weather.R
register_weather_transform.Rd

Adds a named transform to the session registry, the middle tier of the lookup chain weather@misc$transform -> registry -> built-ins. Transforms stored in a weather object's misc$transform list travel with the model and take precedence; the registry serves interactive work and shared helpers. Built-ins identity and scale (weather * wscale) are always available.

Usage

register_weather_transform(name, fun)

Arguments

name

single character, a valid object-name suffix (letters, digits, underscore, starting with a letter). The derived weather object is named <WEATHER>_<name>.

fun

function(weather, ...) -> numeric: weather receives the stream's wval series; ... receives the non-structural columns of the selecting link row as named scalars. Must return a numeric vector of the input's length.

Value

fun, invisibly.

See also

materialize_weather()

Examples

register_weather_transform("power_v112",
  function(weather, wscale = 1, ...) {
    v <- data.frame(speed = c(0, 3, 7, 12, 25, 25.01),
                    af = c(0, 0, 0.4, 1, 1, 0))
    approx(v$speed, v$af, pmax(wscale * weather, 0),
           yleft = 0, yright = 0)$y
  })