Method: Polars::DataFrame#slice

Defined in:
lib/polars/data_frame.rb

#slice(offset, length = nil) ⇒ DataFrame

Get a slice of this DataFrame.

Examples:

df = Polars::DataFrame.new(
  {
    "foo" => [1, 2, 3],
    "bar" => [6.0, 7.0, 8.0],
    "ham" => ["a", "b", "c"]
  }
)
df.slice(1, 2)
# =>
# shape: (2, 3)
# ┌─────┬─────┬─────┐
# │ foo ┆ bar ┆ ham │
# │ --- ┆ --- ┆ --- │
# │ i64 ┆ f64 ┆ str │
# ╞═════╪═════╪═════╡
# │ 2   ┆ 7.0 ┆ b   │
# │ 3   ┆ 8.0 ┆ c   │
# └─────┴─────┴─────┘

Parameters:

  • offset (Integer) —

    Start index. Negative indexing is supported.

  • length (Integer, nil) (defaults to: nil) —

    Length of the slice. If set to nil, all rows starting at the offset will be selected.

Returns:



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# File 'lib/polars/data_frame.rb', line 2191

def slice(offset, length = nil)
  if !length.nil? && length < 0
    length = height - offset + length
  end
  _from_rbdf(_df.slice(offset, length))
end