Method: Polars::Expr#is_null

Defined in:
lib/polars/expr.rb

#is_null ⇒ Expr

Returns a boolean Series indicating which values are null.

Examples:

df = Polars::DataFrame.new(
  {
    "a" => [1, 2, nil, 1, 5],
    "b" => [1.0, 2.0, Float::NAN, 1.0, 5.0]
  }
)
df.with_columns(Polars.all.is_null.name.suffix("_isnull"))
# =>
# shape: (5, 4)
# ┌──────┬─────┬──────────┬──────────┐
# │ a    ┆ b   ┆ a_isnull ┆ b_isnull │
# │ ---  ┆ --- ┆ ---      ┆ ---      │
# │ i64  ┆ f64 ┆ bool     ┆ bool     │
# ╞══════╪═════╪══════════╪══════════╡
# │ 1    ┆ 1.0 ┆ false    ┆ false    │
# │ 2    ┆ 2.0 ┆ false    ┆ false    │
# │ null ┆ NaN ┆ true     ┆ false    │
# │ 1    ┆ 1.0 ┆ false    ┆ false    │
# │ 5    ┆ 5.0 ┆ false    ┆ false    │
# └──────┴─────┴──────────┴──────────┘

Returns:



556
557
558
 
# File 'lib/polars/expr.rb', line 556

def is_null
  wrap_expr(_rbexpr.is_null)
end