Get the byte value at the given index

Description

For example, index 0 would return the first byte of every binary value and index -1 would return the last byte of every binary value.

Usage

<Expr>$bin$get(index, ..., null_on_oob = FALSE)

Arguments

index Index to return per binary value.

… These dots are for future extensions and must be empty.

null_on_oob If TRUE, return null if an index is out of bounds. Otherwise, raise an error.

Value

A polars expression

Examples

library("polars")

df <- pl$DataFrame(x = c("\x01\x02\x03", "", "\x04\x05"))$cast(pl$Binary)

df$with_columns(
  get = pl$col("x")$bin$get(0, null_on_oob = TRUE)
)

#> shape: (3, 2)
#> ┌─────────────────┬──────┐
#> │ x               ┆ get  │
#> │ ---             ┆ ---  │
#> │ binary          ┆ u8   │
#> ╞═════════════════╪══════╡
#> │ b"\x01\x02\x03" ┆ 1    │
#> │ b""             ┆ null │
#> │ b"\x04\x05"     ┆ 4    │
#> └─────────────────┴──────┘