Struct polars_core::prelude::ArrowSchema

pub struct ArrowSchema {
    pub fields: Vec<Field, Global>,
    pub metadata: BTreeMap<String, String, Global>,
}

An ordered sequence of Fields with associated Metadata.

Schema is an abstration used to read from, and write to, Arrow IPC format, Apache Parquet, and Apache Avro. All these formats have a concept of a schema with fields and metadata.

Fields

fields: Vec<Field, Global>

The fields composing this schema.

metadata: BTreeMap<String, String, Global>

Optional metadata.

Implementations

impl Schema

pub fn with_metadata(self, metadata: BTreeMap<String, String, Global>) -> Schema

Attaches a Metadata to Schema

pub fn filter<F>(self, predicate: F) -> Schemawhere F: Fn(usize, &Field) -> bool,

Returns a new Schema with a subset of all fields whose predicate evaluates to true.

Trait Implementations

impl Clone for Schema

fn clone(&self) -> Schema

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Schema

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

Formats the value using the given formatter.

impl Default for Schema

fn default() -> Schema

Returns the “default value” for a type.

impl From<Vec<Field, Global>> for Schema

fn from(fields: Vec<Field, Global>) -> Schema

Converts to this type from the input type.

impl IndexOfSchema for ArrowSchema

fn index_of(&self, name: &str) -> Option<usize>

Get the index of a column by name.

fn get_names(&self) -> Vec<&str>

Get a vector of all column names.

fn try_index_of(&self, name: &str) -> PolarsResult<usize>

impl PartialEq<Schema> for Schema

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

This method tests for self and other values to be equal, and is used by ==.

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

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

impl Eq for Schema

impl StructuralEq for Schema

impl StructuralPartialEq for Schema