Enum PcoDeltaSpec

pub enum PcoDeltaSpec {
    Auto,
    None,
    TryConsecutive {
        delta_encoding_order: PcoDeltaEncodingOrder,
    },
    TryLookback,
}

Pco delta encoding

Variants

Auto

Automatically detects a detects a good delta encoding.

This works well most of the time, but costs some compression time and can select a bad delta encoding in adversarial cases.

None

Never uses delta encoding.

This is best if your data is in a random order or adjacent numbers have no relation to each other.

TryConsecutive

Tries taking nth order consecutive deltas.

Supports a delta encoding order up to 7. For instance, 1st order is just regular delta encoding, 2nd is deltas-of-deltas, etc. It is legal to use 0th order, but it is identical to None.

Fields

delta_encoding_order: PcoDeltaEncodingOrder

the order of the delta encoding

TryLookback

Tries delta encoding according to an extra latent variable of “lookback”.

This can improve compression ratio when there are nontrivial patterns in the array, but reduces compression speed substantially.

Trait Implementations

impl Clone for PcoDeltaSpec

fn clone(&self) -> PcoDeltaSpec

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for PcoDeltaSpec

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for PcoDeltaSpec

fn default() -> PcoDeltaSpec

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for PcoDeltaSpec

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl JsonSchema for PcoDeltaSpec

fn schema_name() -> Cow<'static, str>

The name of the generated JSON Schema.

fn schema_id() -> Cow<'static, str>

Returns a string that uniquely identifies the schema produced by this type.

fn json_schema(generator: &mut SchemaGenerator) -> Schema

Generates a JSON Schema for this type.

fn always_inline_schema() -> bool

Whether JSON Schemas generated for this type should be included directly in parent schemas, rather than being re-used where possible using the $ref keyword.

impl PartialEq for PcoDeltaSpec

fn eq(&self, other: &PcoDeltaSpec) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for PcoDeltaSpec

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Copy for PcoDeltaSpec

impl Eq for PcoDeltaSpec

impl StructuralPartialEq for PcoDeltaSpec