Whether a fire kills a cohort

Dynamic Fire's damage rule for one cohort, vectorised over cells or cohorts. Severity 5 kills every cohort. At severities 1 to 4, the FireDamageTable row that severity minus the species' fire tolerance picks – the row with the largest difference at or below it, as base::findInterval() finds it – gives the oldest cohort killed, as a percentage of longevity, and the cohort dies when its age is at or below that share. Below the table's smallest difference nothing dies. Any other severity, including the 0 of a burned cell in which no cohort was damaged, kills nothing, and so does a missing value in any input.

Usage

fire_cohort_killed(
  severity,
  age,
  longevity,
  tolerance,
  fire_damage_table,
  engine_rule = FALSE
)

Arguments

severity

Numeric. Severity class: a severity map's value minus 2.

age, longevity, tolerance

Numeric. The cohort's age, and its species' longevity and fire tolerance. Each has length 1 or the length of severity.

fire_damage_table

data.frame. The FireDamageTable, in defaultFireDamageTable()'s column order: the percentage of longevity first, severity minus tolerance second. Rows may be in any order.

engine_rule

Logical. Make the age test in single precision, as the extension does?

Value

Logical, one per severity: TRUE where the cohort dies.

Details

By default the age test is made in double precision, 100 * age / longevity <= pct, as landis_overstory_mortality_share() has always made it. With engine_rule = TRUE it is made as the extension makes it (Event.cs, lines 484-490): pct / 100 >= age / longevity, with age / longevity rounded to single precision. The two can differ only where age / longevity is within single-precision rounding of a threshold, as it is when the threshold is a whole number of years: at 10 % of 300 years, a 30-year-old cohort dies by the first test and survives the second.

See also

Other Dynamic Fire calibration helpers: apply_calibrated_damage_age(), apply_calibrated_hi_prop(), apply_calibrated_ignprob(), apply_calibrated_num_fires(), bc_fuel_code_to_base(), bc_fuel_label_to_base(), build_calibration_scenario_template(), build_calibration_spinup_scenario(), calibrate_dynamic_fire(), calibration_par_names(), dedup_community_snapshot(), default_severity_prior_sturtevant2009(), fire_cohort_mortality(), ground_fire_kill_par_names(), landis_dominant_cohorts(), landis_overstory_mortality_share(), loss_from_stats(), observed_fire_sizes(), parse_dynamic_fire_logs(), patch_fire_config(), run_calibration_spinup(), run_calibration_validation(), save_observed_fire_targets(), sim_landis(), sim_mock(), sim_r_reimpl()

Examples

## Tolerance 3 and a 100-year-old cohort of a 300-year species: severity 1 spares it, 2 and 5
## kill it.
fire_cohort_killed(c(1, 2, 5), 100, 300, 3, defaultFireDamageTable())
#> [1] FALSE  TRUE  TRUE