Method: Polars::StringExpr#to_datetime

Defined in:
lib/polars/string_expr.rb

#to_datetime(format = nil, time_unit: nil, time_zone: nil, strict: true, exact: true, cache: true, ambiguous: "raise") ⇒ Expr

Convert a Utf8 column into a Datetime column.

Examples:

s = Polars::Series.new(["2020-01-01 01:00Z", "2020-01-01 02:00Z"])
s.str.to_datetime("%Y-%m-%d %H:%M%#z")
# =>
# shape: (2,)
# Series: '' [datetime[μs, UTC]]
# [
#         2020-01-01 01:00:00 UTC
#         2020-01-01 02:00:00 UTC
# ]

Parameters:

  • format (String) (defaults to: nil) —

    Format to use for conversion. Refer to the chrono crate documentation for the full specification. Example: "%Y-%m-%d %H:%M:%S". If set to nil (default), the format is inferred from the data.

  • time_unit ("us", "ns", "ms") (defaults to: nil) —

    Unit of time for the resulting Datetime column. If set to nil (default), the time unit is inferred from the format string if given, eg: "%F %T%.3f" => Datetime("ms"). If no fractional second component is found, the default is "us".

  • time_zone (String) (defaults to: nil) —

    Time zone for the resulting Datetime column.

  • strict (Boolean) (defaults to: true) —

    Raise an error if any conversion fails.

  • exact (Boolean) (defaults to: true) —

    Require an exact format match. If false, allow the format to match anywhere in the target string.

  • cache (Boolean) (defaults to: true) —

    Use a cache of unique, converted datetimes to apply the conversion.

  • ambiguous ('raise', 'earliest', 'latest', 'null') (defaults to: "raise") —

    Determine how to deal with ambiguous datetimes:

    • 'raise' (default): raise
    • 'earliest': use the earliest datetime
    • 'latest': use the latest datetime
    • 'null': set to null

Returns:



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# File 'lib/polars/string_expr.rb', line 86

def to_datetime(
  format = nil,
  time_unit: nil,
  time_zone: nil,
  strict: true,
  exact: true,
  cache: true,
  ambiguous: "raise"
)
  _validate_format_argument(format)
  unless ambiguous.is_a?(Expr)
    ambiguous = Polars.lit(ambiguous)
  end
  Utils.wrap_expr(
    _rbexpr.str_to_datetime(
      format,
      time_unit,
      time_zone,
      strict,
      exact,
      cache,
      ambiguous._rbexpr
    )
  )
end