Polars

https://docs.rs/polars/latest/polars
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Polars is a high-performance DataFrame library for Rust, built on Apache Arrow's memory model. It...
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### Trim Start Matches Examples

Source: https://docs.rs/polars/latest/polars/datatypes/struct.PlSmallStr.html

Examples of removing prefixes that match a pattern repeatedly.

```rust
assert_eq!("11foo1bar11".trim_start_matches('1'), "foo1bar11");
assert_eq!("123foo1bar123".trim_start_matches(char::is_numeric), "foo1bar123");

let x: &[_] = &['1', '2'];
assert_eq!("12foo1bar12".trim_start_matches(x), "foo1bar12");
```

--------------------------------

### Trim start matches example

Source: https://docs.rs/polars/latest/polars/datatypes/struct.TimeZone.html

Demonstrates trimming characters from the start of a string slice.

```rust
let x: &[_] = &['1', '2'];
assert_eq!("12foo1bar12".trim_start_matches(x), "foo1bar12");
```

--------------------------------

### Column Selection Examples

Source: https://docs.rs/polars/latest/polars/prelude/fn.col.html?search=u32+-%3E+bool

Examples demonstrating how to select columns using direct names, wildcards, or regex patterns.

```rust
// select a column name
col("foo")
```

```rust
// select all columns by using a wildcard
col("*")
```

```rust
// select specific columns by writing a regular expression that starts with `^` and ends with `$`
// only if regex features is activated
col("^foo.*$")
```

--------------------------------

### Created By Field Format Example

Source: https://docs.rs/polars/latest/polars/prelude/struct.FileMetadata.html

Example format for the created_by field string.

```text
parquet-mr version 1.8.0 (build 0fda28af84b9746396014ad6a415b90592a98b3b)
```

--------------------------------

### Initialize DataFrame for GroupBy examples

Source: https://docs.rs/polars/latest/polars/frame/group_by/struct.GroupBy.html

Sets up a DataFrame with date, temperature, and rain columns to be used in subsequent aggregation examples.

```rust
use polars_core::prelude::*;

let dates = &[
"2020-08-21",
"2020-08-21",
"2020-08-22",
"2020-08-23",
"2020-08-22",
];
// date format
let fmt = "%Y-%m-%d";
// create date series
let s0 = DateChunked::parse_from_str_slice("date", dates, fmt)
        .into_series();
// create temperature series
let s1 = Series::new("temp".into(), [20, 10, 7, 9, 1]);
// create rain series
let s2 = Series::new("rain".into(), [0.2, 0.1, 0.3, 0.1, 0.01]);
// create a new DataFrame
let df = DataFrame::new_infer_height(vec![s0, s1, s2]).unwrap();
println!("{:?}", df);
```

--------------------------------

### Trim Matches Examples

Source: https://docs.rs/polars/latest/polars/datatypes/struct.PlSmallStr.html

Examples of removing prefixes and suffixes that match a pattern repeatedly.

```rust
assert_eq!("11foo1bar11".trim_matches('1'), "foo1bar");
assert_eq!("123foo1bar123".trim_matches(char::is_numeric), "foo1bar");

let x: &[_] = &['1', '2'];
assert_eq!("12foo1bar12".trim_matches(x), "foo1bar");
```

```rust
assert_eq!("1foo1barXX".trim_matches(|c| c == '1' || c == 'X'), "foo1bar");
```

--------------------------------

### Strip Prefix Examples

Source: https://docs.rs/polars/latest/polars/datatypes/struct.PlSmallStr.html

Examples of removing a prefix exactly once if it exists.

```rust
assert_eq!("foo:bar".strip_prefix("foo:"), Some("bar"));
assert_eq!("foo:bar".strip_prefix("bar"), None);
assert_eq!("foofoo".strip_prefix("foo"), Some("foo"));
```

--------------------------------

### CollectBatches::start

Source: https://docs.rs/polars/latest/polars/prelude/struct.CollectBatches.html?search=std%3A%3Avec

Starts running the query if it has not already been started.

```APIDOC
## pub fn start(&mut self)

### Description
Starts running the query, if not already started.

### Signature
`pub fn start(&mut self)`
```

--------------------------------

### Trim Prefix Examples

Source: https://docs.rs/polars/latest/polars/datatypes/struct.PlSmallStr.html

Examples of removing an optional prefix using the nightly-only API.

```rust
#![feature(trim_prefix_suffix)]

// Prefix present - removes it
assert_eq!("foo:bar".trim_prefix("foo:"), "bar");
assert_eq!("foofoo".trim_prefix("foo"), "foo");
```

--------------------------------

### Trim End Matches Examples

Source: https://docs.rs/polars/latest/polars/datatypes/struct.PlSmallStr.html

Examples of removing repeated suffixes that match a specific pattern.

```rust
assert_eq!("11foo1bar11".trim_end_matches('1'), "11foo1bar");
assert_eq!("123foo1bar123".trim_end_matches(char::is_numeric), "123foo1bar");

let x: &[_] = &['1', '2'];
assert_eq!("12foo1bar12".trim_end_matches(x), "12foo1bar");
```

```rust
assert_eq!("1fooX".trim_end_matches(|c| c == '1' || c == 'X'), "1foo");
```

--------------------------------

### Create HashSet with Hasher

Source: https://docs.rs/polars/latest/polars/datatypes/type.PlHashSet.html

Examples of initializing a HashSet with a specific hasher.

```rust
use hashbrown::HashSet;
use hashbrown::DefaultHashBuilder;

let s = DefaultHashBuilder::default();
let mut set = HashSet::with_hasher(s);
set.insert(2);
```

```rust
use hashbrown::HashSet;
use hashbrown::DefaultHashBuilder;

let s = DefaultHashBuilder::default();
let mut set = HashSet::with_capacity_and_hasher(10, s);
set.insert(1);
```

--------------------------------

### CloudWriter::start

Source: https://docs.rs/polars/latest/polars/prelude/cloud/cloud_writer/struct.CloudWriter.html

Starts the cloud writing process.

```APIDOC
## CloudWriter::start

### Description
Initiates the writing process for the CloudWriter.

### Signature
`pub async fn start(&mut self) -> Result<(), PolarsError>`
```

--------------------------------

### CloudWriter::start

Source: https://docs.rs/polars/latest/polars/prelude/cloud/cloud_writer/struct.CloudWriter.html?search=u32+-%3E+bool

Starts the cloud writing process.

```APIDOC
### pub async fn start(&mut self) -> Result<(), PolarsError>

Initializes the writing process for the CloudWriter.
```

--------------------------------

### Strip Suffix Examples

Source: https://docs.rs/polars/latest/polars/datatypes/struct.PlSmallStr.html

Examples of removing a suffix exactly once if it exists.

```rust
assert_eq!("bar:foo".strip_suffix(":foo"), Some("bar"));
assert_eq!("bar:foo".strip_suffix("bar"), None);
assert_eq!("foofoo".strip_suffix("foo"), Some("foo"));
```

--------------------------------

### CollectBatches::start

Source: https://docs.rs/polars/latest/polars/prelude/struct.CollectBatches.html?search=Option%3CT%3E%2C+%28T+-%3E+U%29+-%3E+Option%3CU%3E

Initializes the execution of the query if it has not already been started.

```APIDOC
## pub fn start(&mut self)

### Description
Starts running the query associated with the CollectBatches instance, if it is not already running.
```

--------------------------------

### starts_with

Source: https://docs.rs/polars/latest/polars/prelude/cat/struct.CategoricalNameSpace.html?search=std%3A%3Avec

Checks if the categorical values start with a specific prefix.

```APIDOC
## pub fn starts_with(self, prefix: String) -> Expr

### Description
Returns an expression that evaluates to true if the category string starts with the provided prefix.

### Parameters
- **prefix** (String) - The prefix to check against.

### Returns
- **Expr** - A boolean expression.
```

--------------------------------

### explain

Source: https://docs.rs/polars/latest/polars/prelude/struct.LazyFrame.html?search=

Return a String describing the logical plan.

```APIDOC
## pub fn explain(&self, optimized: bool) -> Result<String, PolarsError>

### Description
Return a String describing the logical plan. If `optimized` is `true`, explains the optimized plan. If `optimized` is `false`, explains the naive, un-optimized plan.
```

--------------------------------

### Box::from_raw Examples

Source: https://docs.rs/polars/latest/polars/chunked_array/object/registry/type.BuilderConstructor.html?search=std%3A%3Avec

Demonstrates reconstructing a Box from a raw pointer, either from a previous into_raw call or manual allocation.

```rust
let x = Box::new(5);
let ptr = Box::into_raw(x);
let x = unsafe { Box::from_raw(ptr) };
```

```rust
use std::alloc::{alloc, Layout};

unsafe {
    let ptr = alloc(Layout::new::<i32>()) as *mut i32;
    // In general .write is required to avoid attempting to destruct
    // the (uninitialized) previous contents of `ptr`, though for this
    // simple example `*ptr = 5` would have worked as well.
    ptr.write(5);
    let x = Box::from_raw(ptr);
}
```

--------------------------------

### Manually Create Box from Global Allocator

Source: https://docs.rs/polars/latest/polars/chunked_array/object/registry/type.BuilderConstructor.html?search=

Shows how to allocate memory manually and wrap it in a Box using from_raw.

```rust
use std::alloc::{alloc, Layout};

unsafe {
    let ptr = alloc(Layout::new::<i32>()) as *mut i32;
    // In general .write is required to avoid attempting to destruct
    // the (uninitialized) previous contents of `ptr`, though for this
    // simple example `*ptr = 5` would have worked as well.
    ptr.write(5);
    let x = Box::from_raw(ptr);
}
```

--------------------------------

### Strip Circumfix Examples

Source: https://docs.rs/polars/latest/polars/datatypes/struct.PlSmallStr.html

Examples of removing both a prefix and a suffix exactly once using the nightly-only API.

```rust
#![feature(strip_circumfix)]

assert_eq!("bar:hello:foo".strip_circumfix("bar:", ":foo"), Some("hello"));
assert_eq!("bar:foo".strip_circumfix("foo", "foo"), None);
assert_eq!("foo:bar;".strip_circumfix("foo:", ';'), Some("bar"));
```

--------------------------------

### Importing Polars prelude

Source: https://docs.rs/polars/latest/polars/frame/struct.DataFrame.html

Common tools are available via the prelude.

```rust
use polars_core::prelude::*; // if the crate polars-core is used directly
// use polars::prelude::*;      if the crate polars is used
```

--------------------------------

### Queueing Commands with QueueableCommand

Source: https://docs.rs/polars/latest/polars/prelude/cloud/cloud_writer/struct.CloudWriterIoTraitWrap.html

Demonstrates how to queue multiple print commands and execute them simultaneously by flushing the writer.

```rust
use std::io::{self, Write};
use crossterm::{QueueableCommand, style::Print};

 fn main() -> io::Result<()> {
    let mut stdout = io::stdout();

    // `Print` will executed executed when `flush` is called.
    stdout
        .queue(Print("foo 1\n".to_string()))?
        .queue(Print("foo 2".to_string()))?;

    // some other code (no execution happening here) ...

    // when calling `flush` on `stdout`, all commands will be written to the stdout and therefore executed.
    stdout.flush()?;

    Ok(())

    // ==== Output ====
    // foo 1
    // foo 2
}
```

--------------------------------

### Get subslice safely

Source: https://docs.rs/polars/latest/polars/datatypes/struct.PlSmallStr.html

Use get to retrieve a subslice without panicking, returning None for invalid indices.

```rust
let v = String::from("🗻∈🌏");

assert_eq!(Some("🗻"), v.get(0..4));

// indices not on UTF-8 sequence boundaries
assert!(v.get(1..).is_none());
assert!(v.get(..8).is_none());

// out of bounds
assert!(v.get(..42).is_none());
```

--------------------------------

### CsvReader Initialization

Source: https://docs.rs/polars/latest/polars/prelude/struct.CsvReadOptions.html?search=u32+-%3E+bool

Methods to finalize the configuration and create a CsvReader instance.

```APIDOC
## CsvReader Initialization

### Description
Methods to convert configured CsvReadOptions into a functional CsvReader.

### Methods
- **try_into_reader_with_file_path(path: Option<PathBuf>) -> Result<CsvReader<File>, PolarsError>**: Creates a reader from a file path.
- **into_reader_with_file_handle<R>(reader: R) -> CsvReader<R>**: Creates a reader from a file handle (requires R: MmapBytesReader).
```

--------------------------------

### pub async fn build_object_store

Source: https://docs.rs/polars/latest/polars/prelude/cloud/fn.build_object_store.html?search=std%3A%3Avec

Builds an ObjectStore based on the URL and passed in options. Returns the cloud location and an implementation of the object store.

```APIDOC
## Function: build_object_store

### Description
Builds an `ObjectStore` based on the URL and passed in options. This function is available when the `polars-io` crate feature is enabled.

### Signature
`pub async fn build_object_store(path: PlRefPath, options: Option<&CloudOptions>, glob: bool) -> Result<(CloudLocation, PolarsObjectStore), PolarsError>`

### Parameters
- **path** (PlRefPath) - The path or URL for the object store.
- **options** (Option<&CloudOptions>) - Optional cloud configuration settings.
- **glob** (bool) - Whether to enable globbing for the path.

### Returns
- **Result<(CloudLocation, PolarsObjectStore), PolarsError>** - A tuple containing the `CloudLocation` and the `PolarsObjectStore` implementation, or a `PolarsError` if the operation fails.
```

--------------------------------

### Naive Byte Splitting Example

Source: https://docs.rs/polars/latest/polars/prelude/_csv_read_internal/struct.SplitLines.html?search=Option%3CT%3E%2C+%28T+-%3E+U%29+-%3E+Option%3CU%3E

An example of a naive approach that fails when CSV fields contain embedded newline characters.

```rust
   for line in bytes.split(b'\n') {
```

--------------------------------

### time_ranges(start: Expr, end: Expr, interval: Duration, closed: ClosedWindow) -> Expr

Source: https://docs.rs/polars/latest/polars/prelude/fn.time_ranges.html

Creates a column of time ranges from a start and stop expression.

```APIDOC
## time_ranges

### Description
Creates a column of time ranges from a `start` and `stop` expression.

### Signature
`pub fn time_ranges(start: Expr, end: Expr, interval: Duration, closed: ClosedWindow) -> Expr`

### Requirements
Available on crate features `dtype-time` and `lazy` only.

### Parameters
- **start** (Expr) - The starting expression for the time range.
- **end** (Expr) - The ending expression for the time range.
- **interval** (Duration) - The duration of each interval.
- **closed** (ClosedWindow) - Defines which side of the interval is closed.
```

--------------------------------

### Create HashMap with Capacity and Hasher

Source: https://docs.rs/polars/latest/polars/datatypes/type.PlHashMap.html

Demonstrates creating a HashMap with a pre-allocated capacity and a specific hash builder.

```rust
use hashbrown::HashMap;
use hashbrown::DefaultHashBuilder;

let s = DefaultHashBuilder::default();
let mut map = HashMap::with_capacity_and_hasher(10, s);
assert_eq!(map.len(), 0);
assert!(map.capacity() >= 10);

map.insert(1, 2);
```

--------------------------------

### ParquetObjectStore::from_uri

Source: https://docs.rs/polars/latest/polars/prelude/struct.ParquetObjectStore.html?search=

Initializes a new ParquetObjectStore instance from a given URI.

```APIDOC
## pub async fn from_uri(uri: PlRefPath, options: Option<&CloudOptions>, metadata: Option<Arc<FileMetadata>>) -> Result<ParquetObjectStore, PolarsError>

### Description
Creates a new ParquetObjectStore instance from the provided URI, optionally accepting cloud configuration and existing file metadata.

### Parameters
- **uri** (PlRefPath) - Required - The URI of the Parquet file.
- **options** (Option<&CloudOptions>) - Optional - Configuration options for cloud storage access.
- **metadata** (Option<Arc<FileMetadata>>) - Optional - Pre-fetched file metadata.
```

--------------------------------

### linear_space(start: Expr, end: Expr, num_samples: Expr, closed: ClosedInterval) -> Expr

Source: https://docs.rs/polars/latest/polars/prelude/fn.linear_space.html?search=

Generates a series of equally-spaced points between a start and end expression.

```APIDOC
## linear_space

### Description
Generates a series of equally-spaced points. This function is available when the `lazy` crate feature is enabled.

### Signature
`pub fn linear_space(start: Expr, end: Expr, num_samples: Expr, closed: ClosedInterval) -> Expr`

### Parameters
- **start** (Expr) - The starting value of the sequence.
- **end** (Expr) - The ending value of the sequence.
- **num_samples** (Expr) - The number of points to generate.
- **closed** (ClosedInterval) - Specifies the interval behavior.

### Returns
- **Expr** - An expression representing the generated series of points.
```

--------------------------------

### datetime_range(start, end, interval, num_samples, closed, time_unit, time_zone)

Source: https://docs.rs/polars/latest/polars/prelude/fn.datetime_range.html

Creates a datetime range expression from the provided start, end, interval, and sample count parameters.

```APIDOC
## Function: datetime_range

### Description
Creates a datetime range from `start`, `end`, `interval`, and `num_samples` expressions. This function is available when the `dtype-datetime` and `lazy` crate features are enabled.

### Signature
`pub fn datetime_range(start: Option<Expr>, end: Option<Expr>, interval: Option<Duration>, num_samples: Option<Expr>, closed: ClosedWindow, time_unit: Option<TimeUnit>, time_zone: Option<TimeZone>) -> Result<Expr, PolarsError>`

### Parameters
- **start** (Option<Expr>) - The starting point of the range.
- **end** (Option<Expr>) - The ending point of the range.
- **interval** (Option<Duration>) - The duration between each point in the range.
- **num_samples** (Option<Expr>) - The number of samples to generate.
- **closed** (ClosedWindow) - Defines which boundaries are included in the range.
- **time_unit** (Option<TimeUnit>) - The unit of time for the range.
- **time_zone** (Option<TimeZone>) - The timezone for the range.

### Returns
- **Result<Expr, PolarsError>** - Returns an expression representing the datetime range or a PolarsError if the operation fails.
```

--------------------------------

### date_ranges(start, end, interval, num_samples, closed)

Source: https://docs.rs/polars/latest/polars/prelude/fn.date_ranges.html

Creates a column of date ranges from start, end, interval, and num_samples expressions. This function is available when the 'dtype-date' and 'lazy' features are enabled.

```APIDOC
## Function: date_ranges

### Description
Creates a column of date ranges from `start`, `end`, `interval`, and `num_samples` expressions.

### Signature
`pub fn date_ranges(start: Option<Expr>, end: Option<Expr>, interval: Option<Duration>, num_samples: Option<Expr>, closed: ClosedWindow) -> Result<Expr, PolarsError>`

### Parameters
- **start** (Option<Expr>) - The starting point of the range.
- **end** (Option<Expr>) - The ending point of the range.
- **interval** (Option<Duration>) - The duration between each step in the range.
- **num_samples** (Option<Expr>) - The number of samples to generate.
- **closed** (ClosedWindow) - Defines which boundaries are included in the range.

### Requirements
- **Crate Features**: `dtype-date`, `lazy`
```

--------------------------------

### Initialization Methods

Source: https://docs.rs/polars/latest/polars/prelude/datatypes/type.TimeChunked.html?search=Option%3CT%3E%2C+%28T+-%3E+U%29+-%3E+Option%3CU%3E

Methods for creating new instances of the Logical time type.

```APIDOC
## new(name: PlSmallStr, v: T)

### Description
Initializes a new Logical<TimeType, Int64Type> instance by name and values. Requires the `dtype-time` crate feature.
```

--------------------------------

### datetime_ranges(start, end, interval, num_samples, closed, time_unit, time_zone)

Source: https://docs.rs/polars/latest/polars/prelude/fn.datetime_ranges.html?search=

Creates a column of datetime ranges from start, end, interval, and num_samples expressions. Requires crate features 'dtype-datetime' and 'lazy'.

```APIDOC
## Function: datetime_ranges

### Description
Creates a column of datetime ranges from `start`, `end`, `interval`, and `num_samples` expressions.

### Signature
`pub fn datetime_ranges(start: Option<Expr>, end: Option<Expr>, interval: Option<Duration>, num_samples: Option<Expr>, closed: ClosedWindow, time_unit: Option<TimeUnit>, time_zone: Option<TimeZone>) -> Result<Expr, PolarsError>`

### Parameters
- **start** (Option<Expr>) - The starting datetime expression.
- **end** (Option<Expr>) - The ending datetime expression.
- **interval** (Option<Duration>) - The duration interval between ranges.
- **num_samples** (Option<Expr>) - The number of samples to generate.
- **closed** (ClosedWindow) - Defines the closed window behavior.
- **time_unit** (Option<TimeUnit>) - The time unit for the datetime values.
- **time_zone** (Option<TimeZone>) - The time zone for the datetime values.

### Returns
- **Result<Expr, PolarsError>** - An expression representing the datetime ranges or a PolarsError if the operation fails.
```

--------------------------------

### Create Dummy Variables Example

Source: https://docs.rs/polars/latest/polars/prelude/trait.DataFrameOps.html?search=u32+-%3E+bool

Demonstrates the usage of the to_dummies method to convert categorical data into dummy variables.

```rust
 use polars_core::prelude::*;

 let df = df! {
      "id" => &[1, 2, 3, 1, 2, 3, 1, 1],
      "type" => &["A", "B", "B", "B", "C", "C", "C", "B"],
      "code" => &["X1", "X2", "X3", "X3", "X2", "X2", "X1", "X1"]
  }.unwrap();

  let dummies = df.to_dummies(None, false, false).unwrap();
  println!("{}", dummies);
```

--------------------------------

### update_view(view: View, start: usize, end: usize, val: &str) -> View

Source: https://docs.rs/polars/latest/polars/prelude/fn.update_view.html?search=

Updates a View object by replacing the content within the specified start and end indices with the provided string value.

```APIDOC
## update_view

### Description
Updates a `View` object by replacing the content within the specified range [start, end) with the provided string value.

### Signature
`pub fn update_view(view: View, start: usize, end: usize, val: &str) -> View`

### Requirements
- **Crate Feature**: `polars-ops`

### Parameters
- **view** (View) - The view object to be updated.
- **start** (usize) - The starting index of the range to update.
- **end** (usize) - The ending index of the range to update.
- **val** (&str) - The string value to insert into the specified range.
```

--------------------------------

### Trim Prefix and Suffix Examples

Source: https://docs.rs/polars/latest/polars/datatypes/struct.PlSmallStr.html

Demonstrates removing prefixes and suffixes from string slices, including method chaining.

```rust
// Prefix absent - returns original string
assert_eq!("foo:bar".trim_prefix("bar"), "foo:bar");

// Method chaining example
assert_eq!("<https://example.com/>".trim_prefix('<').trim_suffix('>'), "https://example.com/");
```

```rust
#![feature(trim_prefix_suffix)]

// Suffix present - removes it
assert_eq!("bar:foo".trim_suffix(":foo"), "bar");
assert_eq!("foofoo".trim_suffix("foo"), "foo");

// Suffix absent - returns original string
assert_eq!("bar:foo".trim_suffix("bar"), "bar:foo");

// Method chaining example
assert_eq!("<https://example.com/>".trim_prefix('<').trim_suffix('>'), "https://example.com/");
```

--------------------------------

### tail

Source: https://docs.rs/polars/latest/polars/prelude/struct.Series.html?search=Option%3CT%3E%2C+%28T+-%3E+U%29+-%3E+Option%3CU%3E

Get the tail of the Series.

```APIDOC
## pub fn tail(&self, length: Option<usize>) -> Series

### Description
Get the tail of the Series.
```

--------------------------------

### Sorting a Series with SortOptions

Source: https://docs.rs/polars/latest/polars/chunked_array/ops/sort/options/struct.SortOptions.html

Example demonstrating how to apply custom sorting options to a Series.

```rust
let s = Series::new("a".into(), [Some(5), Some(2), Some(3), Some(4), None].as_ref());
let sorted = s
    .sort(
        SortOptions::default()
            .with_order_descending(true)
            .with_nulls_last(true)
            .with_multithreaded(false),
    )
    .unwrap();
assert_eq!(
    sorted,
    Series::new("a".into(), [Some(5), Some(4), Some(3), Some(2), None].as_ref())
);
```

--------------------------------

### head

Source: https://docs.rs/polars/latest/polars/prelude/struct.Series.html?search=Option%3CT%3E%2C+%28T+-%3E+U%29+-%3E+Option%3CU%3E

Get the head of the Series.

```APIDOC
## pub fn head(&self, length: Option<usize>) -> Series

### Description
Get the head of the Series.
```

--------------------------------

### Create DataFrame

Source: https://docs.rs/polars/latest/polars/docs/eager/index.html

Demonstrates creating DataFrames using the df! macro and from a vector of Columns.

```rust
use polars::prelude::*;
use polars::df;

// use macro
let df = df! [
    "names" => ["a", "b", "c"],
    "values" => [1, 2, 3],
    "values_nulls" => [Some(1), None, Some(3)]
]?;

// from a Vec<Column>
let c1 = Column::new("names".into(), &["a", "b", "c"]);
let c2 = Column::new("values".into(), &[Some(1), None, Some(3)]);
let df = DataFrame::new_infer_height(vec![c1, c2])?;
```

--------------------------------

### product

Source: https://docs.rs/polars/latest/polars/prelude/struct.Series.html?search=Option%3CT%3E%2C+%28T+-%3E+U%29+-%3E+Option%3CU%3E

Get the product of an array.

```APIDOC
## pub fn product(&self) -> Result<Scalar, PolarsError>

### Description
Get the product of an array. If the DataType is one of {Int8, UInt8, Int16, UInt16} the Series is first cast to Int64 to prevent overflow issues.
```

--------------------------------

### last

Source: https://docs.rs/polars/latest/polars/prelude/struct.LazyFrame.html?search=

Get the last row.

```APIDOC
## pub fn last(self) -> LazyFrame

### Description
Get the last row. Equivalent to `self.slice(-1, 1)`.
```

--------------------------------

### Initialize Vector with Custom Allocator

Source: https://docs.rs/polars/latest/polars/frame/group_by/type.GroupsSlice.html?search=

Demonstrates creating a vector with a specific capacity using the System allocator.

```rust
use std::alloc::System;

let mut vec = Vec::with_capacity_in(10, System);

// The vector contains no items, even though it has capacity for more
assert_eq!(vec.len(), 0);
assert!(vec.capacity() >= 10);

// These are all done without reallocating...
for i in 0..10 {
    vec.push(i);
}
assert_eq!(vec.len(), 10);
assert!(vec.capacity() >= 10);

// ...but this may make the vector reallocate
vec.push(11);
assert_eq!(vec.len(), 11);
assert!(vec.capacity() >= 11);

// A vector of a zero-sized type will always over-allocate, since no
// allocation is necessary
let vec_units = Vec::<(), System>::with_capacity_in(10, System);
assert_eq!(vec_units.capacity(), usize::MAX);
```

--------------------------------

### first

Source: https://docs.rs/polars/latest/polars/prelude/struct.LazyFrame.html?search=

Get the first row.

```APIDOC
## pub fn first(self) -> LazyFrame

### Description
Get the first row. Equivalent to `self.slice(0, 1)`.
```

--------------------------------

### Initialize HashSet with capacity and hasher

Source: https://docs.rs/polars/latest/polars/datatypes/type.PlHashSet.html

Creates an empty HashSet with a pre-allocated capacity and a custom hasher.

```rust
use hashbrown::HashSet;
use hashbrown::DefaultHashBuilder;

let s = DefaultHashBuilder::default();
let mut set = HashSet::with_capacity_and_hasher(10, s);
set.insert(1);
```

--------------------------------

### starts_with

Source: https://docs.rs/polars/latest/polars/prelude/trait.BinaryNameSpaceImpl.html?search=std%3A%3Avec

Check if strings starts with a substring.

```APIDOC
## fn starts_with(&self, sub: &[u8]) -> ChunkedArray<BooleanType>

### Description
Check if strings starts with a substring.
```

--------------------------------

### new

Source: https://docs.rs/polars/latest/polars/prelude/type.StringChunkedBuilder.html?search=Option%3CT%3E%2C+%28T+-%3E+U%29+-%3E+Option%3CU%3E

Creates a new instance of the builder with a specified name and capacity.

```APIDOC
## pub fn new(name: PlSmallStr, capacity: usize) -> BinViewChunkedBuilder<T>

### Description
Creates a new BinViewChunkedBuilder instance.

### Parameters
- **name** (PlSmallStr) - The name of the resulting array.
- **capacity** (usize) - Number of string elements in the final array.
```

--------------------------------

### starts_with<P>(pat: P) -> bool

Source: https://docs.rs/polars/latest/polars/datatypes/struct.TimeZone.html?search=std%3A%3Avec

Checks if the string starts with the given pattern.

```APIDOC
## pub fn starts_with<P>(&self, pat: P) -> bool

### Description
Returns `true` if the given pattern matches a prefix of this string slice.
```

--------------------------------

### tail

Source: https://docs.rs/polars/latest/polars/prelude/struct.LazyFrame.html?search=

Get the last n rows.

```APIDOC
## pub fn tail(self, n: u32) -> LazyFrame

### Description
Get the last `n` rows. Equivalent to `self.slice(-(n as i64), n)`.
```

--------------------------------

### get

Source: https://docs.rs/polars/latest/polars/frame/struct.DataFrame.html

Retrieves a row from the DataFrame by index.

```APIDOC
## pub fn get(&self, idx: usize) -> Option<Vec<AnyValue<'_>>>

### Description
Get a row in the `DataFrame`. Beware this is slow.
```

--------------------------------

### linear_spaces(start: Expr, end: Expr, num_samples: Expr, closed: ClosedInterval, as_array: bool) -> Result<Expr, PolarsError>

Source: https://docs.rs/polars/latest/polars/prelude/fn.linear_spaces.html

Creates a column of linearly-spaced sequences from 'start', 'end', and 'num_samples' expressions. This function is available when the 'lazy' feature is enabled.

```APIDOC
## Function: linear_spaces

### Description
Create a column of linearly-spaced sequences from 'start', 'end', and 'num_samples' expressions.

### Signature
`pub fn linear_spaces(start: Expr, end: Expr, num_samples: Expr, closed: ClosedInterval, as_array: bool) -> Result<Expr, PolarsError>`

### Parameters
- **start** (Expr) - The starting value expression.
- **end** (Expr) - The ending value expression.
- **num_samples** (Expr) - The number of samples expression.
- **closed** (ClosedInterval) - Defines the interval closure.
- **as_array** (bool) - Whether to return as an array.

### Requirements
- **Feature Flag**: Requires the `lazy` crate feature.
```

--------------------------------

### Start a lazy computation

Source: https://docs.rs/polars/latest/polars/docs/lazy/index.html

Demonstrates initializing a LazyFrame from an eager DataFrame, a CSV file, or a Parquet file.

```rust
use polars::prelude::*;
use polars::df;

let df = df![
    "a" => [1, 2, 3],
    "b" => [None, Some("a"), Some("b")]
]?;
// from an eager DataFrame
let lf: LazyFrame = df.lazy();

// scan a csv file lazily
let lf: LazyFrame = LazyCsvReader::new("some_path")
    .with_has_header(true)
    .finish()?;

// scan a parquet file lazily
let lf: LazyFrame = LazyFrame::scan_parquet("some_path", Default::default())?;
```

--------------------------------

### Writeable::try_new

Source: https://docs.rs/polars/latest/polars/prelude/file/enum.Writeable.html?search=std%3A%3Avec

Initializes a new Writeable instance based on the provided path and cloud configuration.

```APIDOC
## pub fn try_new(path: PlRefPath, cloud_options: Option<&CloudOptions>, cloud_upload_chunk_size: usize, cloud_upload_concurrency: usize, io_metrics: Option<Arc<IOMetrics>>) -> Result<Writeable, PolarsError>

### Description
Creates a new Writeable instance, abstracting over local or cloud file destinations.

### Parameters
- **path** (PlRefPath) - The target file path.
- **cloud_options** (Option<&CloudOptions>) - Configuration for cloud storage.
- **cloud_upload_chunk_size** (usize) - Chunk size for cloud uploads.
- **cloud_upload_concurrency** (usize) - Concurrency level for cloud uploads.
- **io_metrics** (Option<Arc<IOMetrics>>) - Optional metrics tracking for I/O operations.
```

--------------------------------

### tokio_mkdir_recursive

Source: https://docs.rs/polars/latest/polars/prelude/mkdir/fn.tokio_mkdir_recursive.html?search=

Asynchronously creates a directory and all its parent components.

```APIDOC
## Function: tokio_mkdir_recursive

### Description
Creates a directory and all of its parent components asynchronously. This function is part of the `polars::prelude` module.

### Signature
`pub async fn tokio_mkdir_recursive(path: &PlRefPath) -> Result<(), Error>`

### Requirements
- **Feature Flag**: `polars-io`

### Parameters
- **path** (&PlRefPath) - The path to the directory to be created.
```

--------------------------------

### tokio_mkdir_recursive

Source: https://docs.rs/polars/latest/polars/prelude/mkdir/fn.tokio_mkdir_recursive.html?search=std%3A%3Avec

Asynchronously creates a directory and all its parent components.

```APIDOC
## Function: tokio_mkdir_recursive

### Description
Asynchronously creates a directory and all its parent components. This function is available only when the `polars-io` crate feature is enabled.

### Signature
`pub async fn tokio_mkdir_recursive(path: &PlRefPath) -> Result<(), Error>`

### Parameters
- **path** (&PlRefPath) - The path to the directory to be created.

### Returns
- **Result<(), Error>** - Returns `Ok(())` if the directory was created successfully, or an `Error` if the operation failed.
```

--------------------------------

### size_bytes

Source: https://docs.rs/polars/latest/polars/prelude/trait.BinaryNameSpaceImpl.html?search=Option%3CT%3E%2C+%28T+-%3E+U%29+-%3E+Option%3CU%3E

Get the size of the binary values in bytes.

```APIDOC
## fn size_bytes(&self) -> ChunkedArray<UInt32Type>

### Description
Get the size of the binary values in bytes.
```

--------------------------------

### from_uri

Source: https://docs.rs/polars/latest/polars/prelude/struct.IpcReaderAsync.html?search=Option%3CT%3E%2C+%28T+-%3E+U%29+-%3E+Option%3CU%3E

Initializes a new IpcReaderAsync instance from a given URI and optional cloud configuration.

```APIDOC
### pub async fn from_uri(uri: PlRefPath, cloud_options: Option<&CloudOptions>) -> Result<IpcReaderAsync, PolarsError>

Initializes an asynchronous IPC reader for the specified URI. Requires the `polars-io` feature.
```

--------------------------------

### get

Source: https://docs.rs/polars/latest/polars/prelude/struct.ScratchHashMap.html?search=std%3A%3Avec

Clears the HashMap and returns a mutable reference to it.

```APIDOC
## pub fn get(&mut self) -> &mut HashMap<K, V, RandomState>

### Description
Clears the current ScratchHashMap and returns a mutable reference to the underlying HashMap.

### Signature
`pub fn get(&mut self) -> &mut HashMap<K, V, RandomState>`
```

--------------------------------

### last

Source: https://docs.rs/polars/latest/polars/prelude/struct.NullChunked.html?search=std%3A%3Avec

Get the last element of the Series as a Scalar.

```APIDOC
## fn last(&self) -> Scalar
```

--------------------------------

### Create HashMap with Hasher

Source: https://docs.rs/polars/latest/polars/datatypes/type.PlHashMap.html

Demonstrates creating a HashMap with a specific hash builder.

```rust
use hashbrown::HashMap;
use hashbrown::DefaultHashBuilder;

let s = DefaultHashBuilder::default();
let mut map = HashMap::with_hasher(s);
assert_eq!(map.len(), 0);
assert_eq!(map.capacity(), 0);

map.insert(1, 2);
```

--------------------------------

### first

Source: https://docs.rs/polars/latest/polars/prelude/struct.NullChunked.html?search=std%3A%3Avec

Get the first element of the Series as a Scalar.

```APIDOC
## fn first(&self) -> Scalar
```

--------------------------------

### pub fn mkdir_recursive(path: &PlRefPath) -> Result<(), Error>

Source: https://docs.rs/polars/latest/polars/prelude/mkdir/fn.mkdir_recursive.html

Creates a directory and all its parent components if they do not exist.

```APIDOC
## Function: mkdir_recursive

### Description
Creates a directory and all its parent components if they do not exist. This function is available only when the `polars-io` crate feature is enabled.

### Signature
`pub fn mkdir_recursive(path: &PlRefPath) -> Result<(), Error>`

### Parameters
- **path** (&PlRefPath) - The path to the directory to be created.

### Returns
- **Result<(), Error>** - Returns `Ok(())` if the directory was created successfully, or an `Error` if the operation failed.
```

--------------------------------

### get

Source: https://docs.rs/polars/latest/polars/prelude/struct.NullChunked.html?search=Option%3CT%3E%2C+%28T+-%3E+U%29+-%3E+Option%3CU%3E

Retrieves a single value from the array by its index.

```APIDOC
## fn get(&self, index: usize) -> Result<AnyValue<'_>, PolarsError>

### Description
Get a single value by index. Don’t use this operation for loops as a runtime cast is needed for every iteration.
```

--------------------------------

### CompatLevel::newest

Source: https://docs.rs/polars/latest/polars/datatypes/struct.CompatLevel.html?search=Option%3CT%3E%2C+%28T+-%3E+U%29+-%3E+Option%3CU%3E

Returns the newest compatibility level.

```APIDOC
## pub const fn newest() -> CompatLevel

### Description
Returns the newest compatibility level.
```

--------------------------------

### last(self) -> LazyFrame

Source: https://docs.rs/polars/latest/polars/prelude/struct.LazyFrame.html

Get the last row.

```APIDOC
## last(self) -> LazyFrame

### Description
Get the last row. Equivalent to `self.slice(-1, 1)`.
```

--------------------------------

### first(self) -> LazyFrame

Source: https://docs.rs/polars/latest/polars/prelude/struct.LazyFrame.html

Get the first row.

```APIDOC
## first(self) -> LazyFrame

### Description
Get the first row. Equivalent to `self.slice(0, 1)`.
```

--------------------------------

### Box::new_uninit

Source: https://docs.rs/polars/latest/polars/prelude/type.ArrayRef.html?search=Option%3CT%3E%2C+%28T+-%3E+U%29+-%3E+Option%3CU%3E

Constructs a new box with uninitialized contents.

```APIDOC
## pub fn new_uninit() -> Box<MaybeUninit<T>>

### Description
Constructs a new box with uninitialized contents.
```

--------------------------------

### to_dot

Source: https://docs.rs/polars/latest/polars/prelude/struct.LazyFrame.html?search=

Get a dot language representation of the LogicalPlan.

```APIDOC
## pub fn to_dot(&self, optimized: bool) -> Result<String, PolarsError>

### Description
Get a dot language representation of the LogicalPlan.

### Parameters
- **optimized** (bool) - Whether to return the representation of the optimized plan.
```

--------------------------------

### PrefilterMaskSetting::init_from_env

Source: https://docs.rs/polars/latest/polars/prelude/_internal/enum.PrefilterMaskSetting.html?search=std%3A%3Avec

Initializes a new PrefilterMaskSetting instance based on environment variables.

```APIDOC
## fn init_from_env() -> PrefilterMaskSetting

### Description
Initializes the PrefilterMaskSetting configuration by reading from the environment.

### Returns
- **PrefilterMaskSetting** - The configured setting instance.
```

--------------------------------

### get

Source: https://docs.rs/polars/latest/polars/prelude/struct.Arc.html?search=Option%3CT%3E%2C+%28T+-%3E+U%29+-%3E+Option%3CU%3E

Retrieves the bytes stored at the specified location.

```APIDOC
## async fn get(&self, location: &Path) -> Result<GetResult, Error>

### Description
Return the bytes that are stored at the specified location.

### Parameters
- **location** (&Path) - Required - The path of the object to retrieve.
```

--------------------------------

### Initialization Methods

Source: https://docs.rs/polars/latest/polars/prelude/type.Int32Chunked.html?search=

Methods for initializing ChunkedArray instances.

```APIDOC
## Initialization Methods

### from_iter_values(name: PlSmallStr, it: impl Iterator<Item = <T as PolarsNumericType>::Native>) -> ChunkedArray<T>
Create a new ChunkedArray from an iterator.

### from_slice(name: PlSmallStr, v: &[<T as PolarsNumericType>::Native]) -> ChunkedArray<T>
Create a new ChunkedArray from a slice.

### from_slice_options(name: PlSmallStr, opt_v: &[Option<<T as PolarsNumericType>::Native>]) -> ChunkedArray<T>
Create a new ChunkedArray from a slice of options.

### from_iter_options(name: PlSmallStr, it: impl Iterator<Item = Option<<T as PolarsNumericType>::Native>>) -> ChunkedArray<T>
Create a new ChunkedArray from an iterator of options.
```

--------------------------------

### insert_full

Source: https://docs.rs/polars/latest/polars/datatypes/type.PlIndexSet.html?search=std%3A%3Avec

Insert a value into the set and get its index.

```APIDOC
## pub fn insert_full(&mut self, value: T) -> (usize, bool)

### Description
Insert the value into the set, and get its index. Returns the index and a boolean indicating if it was a new insertion.

### Parameters
- **value** (T) - Required - The value to insert.
```

--------------------------------

### DataFrame Initialization

Source: https://docs.rs/polars/latest/polars/frame/struct.DataFrame.html

Methods for creating a new DataFrame instance, including empty initialization, construction from a vector of columns, and using the df! macro.

```APIDOC
## DataFrame::empty()

### Description
Creates an empty DataFrame with shape (0, 0).

## DataFrame::new_infer_height(columns: Vec<Column>)

### Description
Constructs a DataFrame from a vector of columns, inferring the height from the column lengths.

## df!(...)

### Description
A macro for convenient DataFrame construction using key-value pairs.
```

--------------------------------

### Compare Arc for Ordering

Source: https://docs.rs/polars/latest/polars/chunked_array/object/registry/type.ObjectArrayGetter.html?search=

Demonstrates partial comparison and relational operators for Arc instances.

```rust
use std::sync::Arc;
use std::cmp::Ordering;

let five = Arc::new(5);

assert_eq!(Some(Ordering::Less), five.partial_cmp(&Arc::new(6)));
```

```rust
use std::sync::Arc;

let five = Arc::new(5);

assert!(five < Arc::new(6));
```

```rust
use std::sync::Arc;

let five = Arc::new(5);

assert!(five <= Arc::new(5));
```

```rust
use std::sync::Arc;

let five = Arc::new(5);

assert!(five > Arc::new(4));
```

```rust
use std::sync::Arc;

let five = Arc::new(5);

assert!(five >= Arc::new(5));
```

--------------------------------

### get

Source: https://docs.rs/polars/latest/polars/datatypes/type.PlHashMap.html?search=std%3A%3Avec

Returns a reference to the value corresponding to the key.

```APIDOC
## pub fn get<Q>(&self, k: &Q) -> Option<&V>

### Description
Returns a reference to the value corresponding to the key. The key may be any borrowed form of the map’s key type, but `Hash` and `Eq` on the borrowed form must match those for the key type.
```

--------------------------------

### get_opts

Source: https://docs.rs/polars/latest/polars/chunked_array/object/registry/type.ObjectArrayGetter.html?search=Option%3CT%3E%2C+%28T+-%3E+U%29+-%3E+Option%3CU%3E

Performs a get request with the specified options.

```APIDOC
## fn get_opts

### Description
Performs a get request with the specified options.

### Signature
`fn get_opts<'life0, 'life1, 'async_trait>(&'life0 self, location: &'life1 Path, options: GetOptions) -> Pin<Box<dyn Future<Output = Result<GetResult, Error>> + Send + 'async_trait>>`
```

--------------------------------

### pub fn mkdir_recursive(path: &PlRefPath) -> Result<(), Error>

Source: https://docs.rs/polars/latest/polars/prelude/mkdir/fn.mkdir_recursive.html?search=

Creates a directory and all its parent components recursively.

```APIDOC
## Function: mkdir_recursive

### Description
Creates a directory and all its parent components recursively. This function is available when the `polars-io` feature is enabled.

### Signature
`pub fn mkdir_recursive(path: &PlRefPath) -> Result<(), Error>`

### Parameters
- **path** (&PlRefPath) - The path to the directory to be created.

### Returns
- **Result<(), Error>** - Returns `Ok(())` if the directory was created successfully, or an `Error` if the operation failed.
```

--------------------------------

### slice

Source: https://docs.rs/polars/latest/polars/prelude/struct.CategoricalNameSpace.html?search=std%3A%3Avec

Slices the categorical values starting from a given offset.

```APIDOC
### pub fn slice(self, offset: i64, length: Option<usize>) -> Expr

Returns an expression that slices the categorical values starting at the specified offset with an optional length.
```

--------------------------------

### pub fn mkdir_recursive(path: &PlRefPath) -> Result<(), Error>

Source: https://docs.rs/polars/latest/polars/prelude/mkdir/fn.mkdir_recursive.html?search=std%3A%3Avec

Creates a directory and all its parent components recursively.

```APIDOC
## Function: mkdir_recursive

### Description
Creates a directory and all its parent components recursively. This function is part of the `polars::prelude` module.

### Signature
`pub fn mkdir_recursive(path: &PlRefPath) -> Result<(), Error>`

### Requirements
- **Crate Feature**: `polars-io`

### Parameters
- **path** (&PlRefPath) - The path to the directory to be created.

### Returns
- **Result<(), Error>** - Returns `Ok(())` if the directory was created successfully, or an `Error` if the operation failed.
```

--------------------------------

### pub fn repeat(&self, n: usize) -> String

Source: https://docs.rs/polars/latest/polars/prelude/datatypes/struct.TimeZone.html?search=u32+-%3E+bool

Creates a new String by repeating the original string n times.

```APIDOC
## pub fn repeat(&self, n: usize) -> String

### Description
Creates a new String by repeating a string n times.

### Parameters
- **&self** - The string slice to repeat.
- **n** (usize) - The number of times to repeat the string.

### Panics
This function will panic if the resulting capacity would overflow.

### Returns
- **String** - A new String containing the repeated sequence.
```

--------------------------------

### Check for prefix

Source: https://docs.rs/polars/latest/polars/datatypes/struct.PlSmallStr.html

Checks if the string starts with a specific pattern.

```rust
let bananas = "bananas";

assert!(bananas.starts_with("bana"));
assert!(!bananas.starts_with("nana"));
```

```rust
let bananas = "bananas";

// Note that both of these assert successfully.
assert!(bananas.starts_with(&['b', 'a', 'n', 'a']));
assert!(bananas.starts_with(&['a', 'b', 'c', 'd']));
```

--------------------------------

### Iterate over ChunkedArray

Source: https://docs.rs/polars/latest/polars/chunked_array/struct.ChunkedArray.html

Examples of forward and backward iteration over a ChunkedArray.

```rust
fn iter_forward(ca: &Float32Chunked) {
    ca.iter()
        .for_each(|opt_v| println!("{:?}", opt_v))
}

fn iter_backward(ca: &Float32Chunked) {
    ca.iter()
        .rev()
        .for_each(|opt_v| println!("{:?}", opt_v))
}
```

--------------------------------

### init_from_env

Source: https://docs.rs/polars/latest/polars/prelude/_internal/enum.PrefilterMaskSetting.html?search=Option%3CT%3E%2C+%28T+-%3E+U%29+-%3E+Option%3CU%3E

Initializes a PrefilterMaskSetting instance based on environment variables.

```APIDOC
## pub fn init_from_env() -> PrefilterMaskSetting

### Description
Initializes the PrefilterMaskSetting from the current environment configuration.

### Returns
- **PrefilterMaskSetting** - The initialized setting instance.
```

--------------------------------

### last_non_null

Source: https://docs.rs/polars/latest/polars/prelude/struct.NullChunked.html?search=std%3A%3Avec

Get the last non-null element of the Series as a Scalar.

```APIDOC
## fn last_non_null(&self) -> Scalar
```

--------------------------------

### init_from_env

Source: https://docs.rs/polars/latest/polars/prelude/_internal/enum.PrefilterMaskSetting.html?search=u32+-%3E+bool

Initializes a PrefilterMaskSetting instance based on environment variables.

```APIDOC
## pub fn init_from_env() -> PrefilterMaskSetting

### Description
Initializes the PrefilterMaskSetting configuration by reading from the environment.

### Returns
- **PrefilterMaskSetting** - The configured setting based on environment variables.
```
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