# `HL7v2.Type.DLT`
[🔗](https://github.com/Balneario-de-Cofrentes/hl7v2/blob/v3.10.1/lib/hl7v2/type/dlt.ex#L1)

Delta (DLT) -- HL7v2 composite data type.

Specifies delta check parameters for observation values.

4 components:
1. Normal Range (NR) -- sub-components (low & high)
2. Numeric Threshold (NM)
3. Change Computation (ID) -- percent, absolute
4. Days Retained (NM)

# `t`

```elixir
@type t() :: %HL7v2.Type.DLT{
  change_computation: binary() | nil,
  days_retained: binary() | nil,
  normal_range: HL7v2.Type.NR.t() | nil,
  numeric_threshold: binary() | nil
}
```

# `encode`

```elixir
@spec encode(t() | nil) :: list()
```

Encodes a DLT to a list of component strings.

## Examples

    iex> HL7v2.Type.DLT.encode(%HL7v2.Type.DLT{numeric_threshold: "5", change_computation: "P"})
    ["", "5", "P"]

    iex> HL7v2.Type.DLT.encode(nil)
    []

# `parse`

```elixir
@spec parse(list()) :: t()
```

Parses a DLT from a list of components.

## Examples

    iex> HL7v2.Type.DLT.parse(["2.5&10.0", "5", "P", "7"])
    %HL7v2.Type.DLT{
      normal_range: %HL7v2.Type.NR{
        low: %HL7v2.Type.NM{value: "2.5", original: "2.5"},
        high: %HL7v2.Type.NM{value: "10", original: "10.0"}
      },
      numeric_threshold: "5",
      change_computation: "P",
      days_retained: "7"
    }

    iex> HL7v2.Type.DLT.parse([])
    %HL7v2.Type.DLT{}

---

*Consult [api-reference.md](api-reference.md) for complete listing*