Build a Spatial Design Matrix from a Data Frame — build_design

Places each treatment value at the grid position given by its row_column and col_column coordinates, returning a character matrix of dimensions max(row) by max(col). Cells with no corresponding row in df are NA.

Each plot's position comes from its own coordinates, so the row ordering of df is irrelevant, as is the level order of factor coordinate columns.

Coordinates are used as-is, never renumbered: a gap in the coordinates is a real gap in the field (a missing plot, or a buffer that was removed), so collapsing it would make non-adjacent plots into neighbours. Callers must therefore cope with NA cells.

Usage

build_design_matrix(
  df,
  swap,
  row_column = "row",
  col_column = "col",
  index = NULL
)

Arguments

df: A data frame with columns named by swap, row_column, col_column.
swap: Column name of the treatment variable.
row_column: Column name of the row position variable (default "row").
col_column: Column name of the column position variable (default "col").
index: Optional pre-built index from grid_index(). Supplying one skips coordinate coercion and validation, which is the bulk of the work and is invariant during annealing. speed() builds one per run; anything calling this once should leave it NULL.

Value

A character matrix of dimensions max(row) by max(col).