joustava
Genetic Algorithms in Elixir: Chapter 6: Misplaced parenthesis in fitness_function (page 90)
Seems that in the line:
|> Kernel.-(Enum.at(chromosome.genes), j)
the closing parens (after genes) is misplaced.
should probably be
|> Kernel.-(Enum.at(chromosome.genes, j))
Otherwise we get a
** (UndefinedFunctionError) function Enum.at/1 is undefined or private. Did you mean one of:
* at/2
* at/3
(elixir 1.10.3) Enum.at([3, 7, 5, 2, 1, 0, 6, 4])
scripts/n_queens.exs:21: anonymous fn/4 in NQueens.fitness_function/1
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