Load Habitat Model Parameter Sets

Load species-specific habitat thresholds from a PostgreSQL table or a local CSV file. Returns a list of parameter sets, one per species, ready for iteration with lapply() or purrr::walk() over the frs_break() / frs_classify() pipeline.

Usage

frs_params(
  conn = NULL,
  table = "bcfishpass.parameters_habitat_thresholds",
  csv = NULL
)

Arguments

conn

A DBI::DBIConnection object (from frs_db_conn()). Required when reading from a database table. Use NULL when reading from a CSV file.

table

Character. Schema-qualified table name to read parameters from. Default "bcfishpass.parameters_habitat_thresholds".

csv

Character or NULL. Path to a local CSV file. When provided, conn and table are ignored.

Value

A named list of parameter sets, keyed by species code. Each element is a list with threshold values and a ranges sub-list suitable for passing to frs_classify().

Examples

# Load species thresholds from bundled test data
params <- frs_params(csv = system.file("testdata", "test_params.csv",
  package = "fresh"))
names(params)
#> [1] "BT" "CH" "CO"

# Coho spawning: gradient 0-5.5%, channel width 2m+, MAD 0.16-9999 m3/s
params$CO$ranges$spawn
#> $gradient
#> [1] 0.0000 0.0549
#> 
#> $channel_width
#> [1]    2 9999
#> 
#> $mad_m3s
#> [1]    0.164 9999.000
#> 

# Bull trout rearing: no gradient or MAD constraint, just channel width 1.5m+
params$BT$ranges$rear
#> $channel_width
#> [1]    1.5 9999.0
#> 

if (FALSE) { # \dontrun{
conn <- frs_db_conn()

# Default: bcfishpass parameter tables (11 species)
params <- frs_params(conn)

# Drive the pipeline — one iteration per species
lapply(params, function(p) {
  message(p$species_code, ": gradient max = ", p$spawn_gradient_max)
  # frs_break(conn, ..., threshold = p$spawn_gradient_max)
  # frs_classify(conn, ..., ranges = p$ranges$spawn)
})

DBI::dbDisconnect(conn)
} # }