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Create Transition Metadata Table

Source: R/trans_meta_t.R
trans_meta_t.Rd

Creates a trans_meta_t table based on observed land use transitions in the LULC data. This function analyzes transition patterns and creates metadata entries for each viable transition type.

Usage

as_trans_meta_t(x)

create_trans_meta_t(
  transitions,
  min_cardinality_abs = NULL,
  min_frequency_rel = NULL,
  exclude_anterior = NULL,
  exclude_posterior = NULL
)

# S3 method for class 'trans_meta_t'
print(x, nrow = 10, ...)

Arguments

transitions

A transitions_v table, with columns id_coord, id_lulc_anterior, id_lulc_posterior, id_period

min_cardinality_abs

Minimum absolute number of transitions for viability (optional)

min_frequency_rel

Minimum relative frequency of transitions for viability (optional)

exclude_anterior

Vector of id_lulc values to exclude as anterior (source) classes

exclude_posterior

Vector of id_lulc values to exclude as posterior (target) classes

nrow

see data.table::print.data.table

...

passed to data.table::print.data.table

Value

A data.table of class "trans_meta_t" with columns:

  • id_trans: Unique ID for each transition

  • id_lulc_anterior: Foreign key to lulc_meta_t (before transition)

  • id_lulc_posterior: Foreign key to lulc_meta_t (after transition)

  • cardinality: How many times this transition occurred

  • frequency_rel: Frequency relative to all transitions

  • frequency_abs: Frequency relative to all coordinate pairs

  • is_viable: Whether this transition is viable for modelling

Methods (by generic)

  • print(trans_meta_t): Print a trans_meta_t object, passing params to data.table print

Functions

  • create_trans_meta_t(): Calculate the transition metadata and mark for modelling feasibility. Does not attribute id_trans; this only makes sense as part of a DB.