Method: Polars::Expr#exclude

Defined in:

lib/polars/expr.rb

#exclude(columns) ⇒ Expr

Exclude certain columns from a wildcard/regex selection.

You may also use regexes in the exclude list. They must start with ^ and end with $.

Examples:

df = Polars::DataFrame.new(
  {
    "aa" => [1, 2, 3],
    "ba" => ["a", "b", nil],
    "cc" => [nil, 2.5, 1.5]
  }
)
df.select(Polars.all.exclude("ba"))
# =>
# shape: (3, 2)
# ┌─────┬──────┐
# │ aa  ┆ cc   │
# │ --- ┆ ---  │
# │ i64 ┆ f64  │
# ╞═════╪══════╡
# │ 1   ┆ null │
# │ 2   ┆ 2.5  │
# │ 3   ┆ 1.5  │
# └─────┴──────┘

Parameters:

• columns (Object) —

  Column(s) to exclude from selection. This can be:

  • a column name, or multiple column names
  • a regular expression starting with ^ and ending with $
  • a dtype or multiple dtypes

Returns:

• (Expr)

# File 'lib/polars/expr.rb', line 365

def exclude(columns)
  if columns.is_a?(::String)
    columns = [columns]
    return _from_rbexpr(_rbexpr.exclude(columns))
  elsif !columns.is_a?(::Array)
    columns = [columns]
    return _from_rbexpr(_rbexpr.exclude_dtype(columns))
  end

  if !columns.all? { |a| a.is_a?(::String) } || !columns.all? { |a| Utils.is_polars_dtype(a) }
    raise ArgumentError, "input should be all string or all DataType"
  end

  if columns[0].is_a?(::String)
    _from_rbexpr(_rbexpr.exclude(columns))
  else
    _from_rbexpr(_rbexpr.exclude_dtype(columns))
  end
end