Method: Statsample::FormulaWrapper#initialize

Defined in:
lib/statsample/formula/formula.rb

#initialize(formula, df) ⇒ FormulaWrapper

Note:

Specify 0 as a term in the formula if you do not want constant to be included in the parsed formula

Initializes formula wrapper object to parse a given formula into some tokens which do not overlap one another.

Examples:

df = Daru::DataFrame.from_csv 'spec/data/df.csv'
df.to_category 'c', 'd', 'e'
formula = Statsample::GLM::FormulaWrapper.new 'y~a+d:c', df
formula.canonical_to_s
#=> "1+c(-)+d(-):c+a"

Parameters:

  • formula (string) —

    to parse

  • df (Daru::DataFrame) —

    dataframe requried to know what vectors are numerical

[View source] [View on GitHub]

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# File 'lib/statsample/formula/formula.rb', line 21

def initialize(formula, df)
  @df = df
  # @y store the LHS term that is name of vector to be predicted
  # @tokens store the RHS terms of the formula
  @y, *@tokens = split_to_tokens(formula)
  @tokens = @tokens.uniq.sort
  manage_constant_term
  @canonical_tokens = non_redundant_tokens
end