[][src]Struct polars::frame::DataFrame

pub struct DataFrame { /* fields omitted */ }

Implementations

impl DataFrame[src]

pub fn groupby(&self, by: &str) -> Result<GroupBy<'_>>[src]

Group DataFrame using a Series column.

Example

use polars::prelude::*;
fn groupby_sum(df: &DataFrame) -> Result<DataFrame> {
    df.groupby("column_name")?
    .select("agg_column_name")
    .sum()
}

impl DataFrame[src]

pub fn inner_join(
    &self,
    other: &DataFrame,
    left_on: &str,
    right_on: &str
) -> Result<DataFrame>
[src]

Perform an inner join on two DataFrames.

Example

use polars::prelude::*;
fn join_dfs(left: &DataFrame, right: &DataFrame) -> Result<DataFrame> {
    left.inner_join(right, "join_column_left", "join_column_right")
}

pub fn left_join(
    &self,
    other: &DataFrame,
    left_on: &str,
    right_on: &str
) -> Result<DataFrame>
[src]

Perform a left join on two DataFrames

Example

use polars::prelude::*;
fn join_dfs(left: &DataFrame, right: &DataFrame) -> Result<DataFrame> {
    left.left_join(right, "join_column_left", "join_column_right")
}

pub fn outer_join(
    &self,
    other: &DataFrame,
    left_on: &str,
    right_on: &str
) -> Result<DataFrame>
[src]

Perform an outer join on two DataFrames

Example

use polars::prelude::*;
fn join_dfs(left: &DataFrame, right: &DataFrame) -> Result<DataFrame> {
    left.outer_join(right, "join_column_left", "join_column_right")
}

impl DataFrame[src]

pub fn new(columns: Vec<Series>) -> Result<Self>[src]

Create a DataFrame from a Vector of Series.

Example

use polars::prelude::*;
let s0 = Series::new("days", [0, 1, 2].as_ref());
let s1 = Series::new("temp", [22.1, 19.9, 7.].as_ref());
let df = DataFrame::new(vec![s0, s1]).unwrap();

pub fn schema(&self) -> &Arc<Schema>[src]

Get a reference to the DataFrame schema.

pub fn get_columns(&self) -> &Vec<Series>[src]

Get a reference to the DataFrame columns.

pub fn columns(&self) -> Vec<&str>[src]

Get the column labels of the DataFrame.

pub fn n_chunks(&self) -> Result<usize>[src]

The number of chunks per column

pub fn fields(&self) -> &Vec<Field>[src]

Get a reference the schema fields of the DataFrame.

pub fn shape(&self) -> (usize, usize)[src]

Get (width x height)

Example

use polars::prelude::*;
fn assert_shape(df: &DataFrame, shape: (usize, usize)) {
    assert_eq!(df.shape(), shape)
}

pub fn width(&self) -> usize[src]

Get width of DataFrame

Example

use polars::prelude::*;
fn assert_width(df: &DataFrame, width: usize) {
    assert_eq!(df.width(), width)
}

pub fn height(&self) -> usize[src]

Get height of DataFrame

Example

use polars::prelude::*;
fn assert_height(df: &DataFrame, height: usize) {
    assert_eq!(df.height(), height)
}

pub fn hstack(&mut self, columns: &[Series]) -> Result<()>[src]

Add series column to DataFrame

Example

use polars::prelude::*;
fn stack(df: &mut DataFrame, columns: &[Series]) {
    df.hstack(columns);
}

pub fn drop_in_place(&mut self, name: &str) -> Result<Series>[src]

Remove column by name

Example

use polars::prelude::*;
fn drop_column(df: &mut DataFrame, name: &str) -> Result<Series> {
    df.drop_in_place(name)
}

pub fn drop(&self, name: &str) -> Result<DataFrame>[src]

Drop a column by name. This is a pure method and will return a new DataFrame instead of modifying the current one in place.

pub fn get(&self, idx: usize) -> Option<Vec<AnyType<'_>>>[src]

Get a row in the dataframe. Beware this is slow.

Example

use polars::prelude::*;
fn example(df: &mut DataFrame, idx: usize) -> Option<Vec<AnyType>> {
    df.get(idx)
}

pub fn select_idx(&self, idx: usize) -> Option<&Series>[src]

Select a series by index.

pub fn f_select_idx(&self, idx: usize) -> &Series[src]

Force select.

pub fn select_idx_mut(&mut self, idx: usize) -> Option<&mut Series>[src]

Select a mutable series by index.

pub fn f_select_idx_mut(&mut self, idx: usize) -> &mut Series[src]

Force select.

pub fn find_idx_by_name(&self, name: &str) -> Option<usize>[src]

Get column index of a series by name.

pub fn column(&self, name: &str) -> Option<&Series>[src]

Select a single column by name.

pub fn f_column(&self, name: &str) -> &Series[src]

Force select a single column.

pub fn select<'a, S>(&self, selection: S) -> Result<DataFrame> where
    S: Selection<'a>, 
[src]

Select column(s) from this DataFrame.

Examples

use polars::prelude::*;

fn example(df: &DataFrame, possible: &str) -> Result<DataFrame> {
    match possible {
        "by_str" => df.select("my-column"),
        "by_tuple" => df.select(("col_1", "col_2")),
        "by_vec" => df.select(vec!["col_a", "col_b"]),
         _ => unimplemented!()
    }
}

pub fn select_mut(&mut self, name: &str) -> Option<&mut Series>[src]

Select a mutable series by name.

pub fn f_select_mut(&mut self, name: &str) -> &mut Series[src]

Force select.

pub fn filter(&self, mask: &BooleanChunked) -> Result<Self>[src]

Take DataFrame rows by a boolean mask.

pub fn f_filter(&self, mask: &BooleanChunked) -> Self[src]

Force filter

pub fn take_iter<I>(&self, iter: I, capacity: Option<usize>) -> Result<Self> where
    I: Iterator<Item = usize> + Clone + Sync
[src]

Take DataFrame value by indexes from an iterator.

Example

use polars::prelude::*;
fn example(df: &DataFrame) -> Result<DataFrame> {
    let iterator = (0..9).into_iter();
    df.take_iter(iterator, None)
}

pub unsafe fn take_iter_unchecked<I>(
    &self,
    iter: I,
    capacity: Option<usize>
) -> Self where
    I: Iterator<Item = usize> + Clone + Sync
[src]

Take DataFrame values by indexes from an iterator. This doesn't do any bound checking.

Example

use polars::prelude::*;
unsafe fn example(df: &DataFrame) -> DataFrame {
    let iterator = (0..9).into_iter();
    df.take_iter_unchecked(iterator, None)
}

pub fn take_opt_iter<I>(&self, iter: I, capacity: Option<usize>) -> Result<Self> where
    I: Iterator<Item = Option<usize>> + Clone + Sync
[src]

Take DataFrame values by indexes from an iterator that may contain None values.

Example

use polars::prelude::*;
fn example(df: &DataFrame) -> Result<DataFrame> {
    let iterator = (0..9).into_iter().map(Some);
    df.take_opt_iter(iterator, None)
}

pub unsafe fn take_opt_iter_unchecked<I>(
    &self,
    iter: I,
    capacity: Option<usize>
) -> Self where
    I: Iterator<Item = Option<usize>> + Clone + Sync
[src]

Take DataFrame values by indexes from an iterator that may contain None values. This doesn't do any bound checking.

Example

use polars::prelude::*;
unsafe fn example(df: &DataFrame) -> DataFrame {
    let iterator = (0..9).into_iter().map(Some);
    df.take_opt_iter_unchecked(iterator, None)
}

pub fn take<T: AsTakeIndex + Sync>(&self, indices: &T) -> Result<Self>[src]

Take DataFrame rows by index values.

Example

use polars::prelude::*;
fn example(df: &DataFrame) -> Result<DataFrame> {
    let idx = vec![0, 1, 9];
    df.take(&idx)
}

pub fn f_take<T: AsTakeIndex + Sync>(&self, indices: &T) -> Self[src]

Force take

pub fn rename(&mut self, column: &str, name: &str) -> Result<()>[src]

Rename a column in the DataFrame

Example

use polars::prelude::*;
fn example(df: &mut DataFrame) -> Result<()> {
    let original_name = "foo";
    let new_name = "bar";
    df.rename(original_name, new_name)
}

pub fn sort_in_place(&mut self, by_column: &str, reverse: bool) -> Result<()>[src]

Sort DataFrame in place by a column.

pub fn sort(&self, by_column: &str, reverse: bool) -> Result<Self>[src]

Return a sorted clone of this DataFrame.

pub fn replace(&mut self, column: &str, new_col: Series) -> Result<()>[src]

Replace a column with a series.

pub fn slice(&self, offset: usize, length: usize) -> Result<Self>[src]

Slice the DataFrame along the rows.

pub fn head(&self, length: Option<usize>) -> Self[src]

Get the head of the DataFrame

pub fn tail(&self, length: Option<usize>) -> Self[src]

Get the tail of the DataFrame

pub fn as_record_batches(&self) -> Result<Vec<RecordBatch>>[src]

Transform the underlying chunks in the DataFrame to Arrow RecordBatches

pub fn iter_record_batches(
    &mut self,
    buffer_size: usize
) -> impl Iterator<Item = RecordBatch> + '_
[src]

pub fn reverse(&self) -> Self[src]

Get a DataFrame with all the columns in reversed order

pub fn shift(&self, periods: i32) -> Result<Self>[src]

Shift the values by a given period and fill the parts that will be empty due to this operation with Nones.

See the method on Series for more info on the shift operation.

pub fn fill_none(&self, strategy: FillNoneStrategy) -> Result<Self>[src]

Replace None values with one of the following strategies:

  • Forward fill (replace None with the previous value)
  • Backward fill (replace None with the next value)
  • Mean fill (replace None with the mean of the whole array)
  • Min fill (replace None with the minimum of the whole array)
  • Max fill (replace None with the maximum of the whole array)

See the method on Series for more info on the fill_none operation.

impl DataFrame[src]

pub fn frame_equal(&self, other: &DataFrame) -> bool[src]

Trait Implementations

impl Clone for DataFrame[src]

impl Debug for DataFrame[src]

impl Display for DataFrame[src]

Auto Trait Implementations

Blanket Implementations

impl<T> Any for T where
    T: 'static + ?Sized
[src]

impl<T> Borrow<T> for T where
    T: ?Sized
[src]

impl<T> BorrowMut<T> for T where
    T: ?Sized
[src]

impl<T> From<T> for T[src]

impl<T, U> Into<U> for T where
    U: From<T>, 
[src]

impl<T> ToOwned for T where
    T: Clone
[src]

type Owned = T

The resulting type after obtaining ownership.

impl<T> ToString for T where
    T: Display + ?Sized
[src]

impl<T, U> TryFrom<U> for T where
    U: Into<T>, 
[src]

type Error = Infallible

The type returned in the event of a conversion error.

impl<T, U> TryInto<U> for T where
    U: TryFrom<T>, 
[src]

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.

impl<V, T> VZip<V> for T where
    V: MultiLane<T>,