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Decode values using the provided encoding

Source code

Description

Decode values using the provided encoding

Usage

<Expr>$bin$decode(encoding, ..., strict = TRUE)

Arguments

encoding A character, “hex” or “base64”. The encoding to use.
… Ignored.
strict Raise an error if the underlying value cannot be decoded, otherwise mask out with a null value.

Value

Expr of data type String.

Examples

library("polars")

df = pl$DataFrame(
  name = c("black", "yellow", "blue"),
  code_hex = as_polars_series(c("000000", "ffff00", "0000ff"))$cast(pl$Binary),
  code_base64 = as_polars_series(c("AAAA", "//8A", "AAD/"))$cast(pl$Binary)
)

df$with_columns(
  decoded_hex = pl$col("code_hex")$bin$decode("hex"),
  decoded_base64 = pl$col("code_base64")$bin$decode("base64")
)

#> shape: (3, 5)
#> ┌────────┬───────────┬─────────────┬─────────────────┬─────────────────┐
#> │ name   ┆ code_hex  ┆ code_base64 ┆ decoded_hex     ┆ decoded_base64  │
#> │ ---    ┆ ---       ┆ ---         ┆ ---             ┆ ---             │
#> │ str    ┆ binary    ┆ binary      ┆ binary          ┆ binary          │
#> ╞════════╪═══════════╪═════════════╪═════════════════╪═════════════════╡
#> │ black  ┆ b"000000" ┆ b"AAAA"     ┆ b"\x00\x00\x00" ┆ b"\x00\x00\x00" │
#> │ yellow ┆ b"ffff00" ┆ b"//8A"     ┆ b"\xff\xff\x00" ┆ b"\xff\xff\x00" │
#> │ blue   ┆ b"0000ff" ┆ b"AAD/"     ┆ b"\x00\x00\xff" ┆ b"\x00\x00\xff" │
#> └────────┴───────────┴─────────────┴─────────────────┴─────────────────┘

# Set `strict = FALSE` to set invalid values to `null` instead of raising an error.
df = pl$DataFrame(
  colors = as_polars_series(c("000000", "ffff00", "invalid_value"))$cast(pl$Binary)
)
df$select(pl$col("colors")$bin$decode("hex", strict = FALSE))

#> shape: (3, 1)
#> ┌─────────────────┐
#> │ colors          │
#> │ ---             │
#> │ binary          │
#> ╞═════════════════╡
#> │ b"\x00\x00\x00" │
#> │ b"\xff\xff\x00" │
#> │ null            │
#> └─────────────────┘