Struct polars_core::series::Series [−][src]
pub struct Series(pub Arc<dyn SeriesTrait>);
Expand description
Series
The columnar data type for a DataFrame.
Most of the available functions are definedin the SeriesTrait trait.
The Series
struct consists
of typed ChunkedArray’s. To quickly cast
a Series
to a ChunkedArray
you can call the method with the name of the type:
let s: Series = [1, 2, 3].iter().collect();
// Quickly obtain the ChunkedArray wrapped by the Series.
let chunked_array = s.i32().unwrap();
Arithmetic
You can do standard arithmetic on series.
let s: Series = [1, 2, 3].iter().collect();
let out_add = &s + &s;
let out_sub = &s - &s;
let out_div = &s / &s;
let out_mul = &s * &s;
Or with series and numbers.
let s: Series = (1..3).collect();
let out_add_one = &s + 1;
let out_multiply = &s * 10;
// Could not overload left hand side operator.
let out_divide = 1.div(&s);
let out_add = 1.add(&s);
let out_subtract = 1.sub(&s);
let out_multiply = 1.mul(&s);
Comparison
You can obtain boolean mask by comparing series.
use itertools::Itertools;
let s = Series::new("dollars", &[1, 2, 3]);
let mask = s.eq(1);
let valid = [true, false, false].iter();
assert!(mask
.into_iter()
.map(|opt_bool| opt_bool.unwrap()) // option, because series can be null
.zip(valid)
.all(|(a, b)| a == *b))
See all the comparison operators in the CmpOps trait
Iterators
The Series variants contain differently typed ChunkedArray’s. These structs can be turned into iterators, making it possible to use any function/ closure you want on a Series.
These iterators return an Option<T>
because the values of a series may be null.
use polars_core::prelude::*;
let pi = 3.14;
let s = Series::new("angle", [2f32 * pi, pi, 1.5 * pi].as_ref());
let s_cos: Series = s.f32()
.expect("series was not an f32 dtype")
.into_iter()
.map(|opt_angle| opt_angle.map(|angle| angle.cos()))
.collect();
Creation
Series can be create from different data structures. Below we’ll show a few ways we can create a Series object.
// Series van be created from Vec's, slices and arrays
Series::new("boolean series", &vec![true, false, true]);
Series::new("int series", &[1, 2, 3]);
// And can be nullable
Series::new("got nulls", &[Some(1), None, Some(2)]);
// Series can also be collected from iterators
let from_iter: Series = (0..10)
.into_iter()
.collect();
Tuple Fields
0: Arc<dyn SeriesTrait>
Implementations
diff
only.This is supported on crate feature moment
only.
moment
only.Compute the sample skewness of a data set.
For normally distributed data, the skewness should be about zero. For
unimodal continuous distributions, a skewness value greater than zero means
that there is more weight in the right tail of the distribution. The
function skewtest
can be used to determine if the skewness value
is close enough to zero, statistically speaking.
see: https://github.com/scipy/scipy/blob/47bb6febaa10658c72962b9615d5d5aa2513fa3a/scipy/stats/stats.py#L1024
This is supported on crate feature moment
only.
moment
only.Compute the kurtosis (Fisher or Pearson) of a dataset.
Kurtosis is the fourth central moment divided by the square of the
variance. If Fisher’s definition is used, then 3.0 is subtracted from
the result to give 0.0 for a normal distribution.
If bias is false
then the kurtosis is calculated using k statistics to
eliminate bias coming from biased moment estimators
see: https://github.com/scipy/scipy/blob/47bb6febaa10658c72962b9615d5d5aa2513fa3a/scipy/stats/stats.py#L1027
Convert the values of this Series to a ListChunked with a length of 1,
So a Series of:
[1, 2, 3]
becomes [[1, 2, 3]]
Shrink the capacity of this array to fit it’s length.
Append arrow array of same datatype.
Append a Series of the same type in place.
Sort in place.
Rechunk and return a pointer to the start of the Series. Only implemented for numeric types
Returns None
if the array is empty or only contains null values.
let s = Series::new("days", [1, 2, 3].as_ref());
assert_eq!(s.sum(), Some(6));
Returns the minimum value in the array, according to the natural order. Returns an option because the array is nullable.
let s = Series::new("days", [1, 2, 3].as_ref());
assert_eq!(s.min(), Some(1));
Returns the maximum value in the array, according to the natural order. Returns an option because the array is nullable.
let s = Series::new("days", [1, 2, 3].as_ref());
assert_eq!(s.max(), Some(3));
Explode a list or utf8 Series. This expands every item to a new row..
Check if float value is NaN (note this is different than missing/ null)
Check if float value is NaN (note this is different than missing/ null)
Check if float value is finite
Check if float value is finite
This is supported on crate feature zip_with
only.
zip_with
only.Create a new ChunkedArray with values from self where the mask evaluates true
and values
from other
where the mask evaluates false
Cast a datelike Series to their physical representation. Primitives remain unchanged
- Date -> Int32
- Datetime-> Int64
pub unsafe fn take_unchecked_threaded(
&self,
idx: &UInt32Chunked,
rechunk: bool
) -> Result<Series>
pub unsafe fn take_unchecked_threaded(
&self,
idx: &UInt32Chunked,
rechunk: bool
) -> Result<Series>
Take by index if ChunkedArray contains a single chunk.
Safety
This doesn’t check any bounds. Null validity is checked.
Take by index. This operation is clone.
Safety
Out of bounds access doesn’t Error but will return a Null value
Filter by boolean mask. This operation clones data.
This is supported on crate feature round_series
only.
round_series
only.Round underlying floating point array to given decimal.
This is supported on crate feature round_series
only.
round_series
only.Floor underlying floating point array to the lowest integers smaller or equal to the float value.
dot_product
only.This is supported on crate feature row_hash
only.
row_hash
only.Get a hash of this Series
This is supported on crate feature cum_agg
only.
cum_agg
only.Get an array with the cumulative max computed at every element
This is supported on crate feature cum_agg
only.
cum_agg
only.Get an array with the cumulative min computed at every element
This is supported on crate feature cum_agg
only.
cum_agg
only.Get an array with the cumulative sum computed at every element
This is supported on crate feature cum_agg
only.
cum_agg
only.Get an array with the cumulative product computed at every element
This is supported on crate feature rolling_window
only.
rolling_window
only.Apply a rolling variance to a Series. See:
This is supported on crate feature rolling_window
only.
rolling_window
only.Apply a rolling std to a Series. See:
This is supported on crate feature rolling_window
only.
rolling_window
only.Apply a rolling mean to a Series. See: ChunkedArray::rolling_mean.
This is supported on crate feature rolling_window
only.
rolling_window
only.Apply a rolling sum to a Series. See: ChunkedArray::rolling_sum.
This is supported on crate feature rolling_window
only.
rolling_window
only.Apply a rolling min to a Series. See: ChunkedArray::rolling_min.
This is supported on crate feature rolling_window
only.
rolling_window
only.Apply a rolling max to a Series. See: ChunkedArray::rolling_max.
rank
only.Cast throws an error if conversion had overflows
Check if series are equal. Note that None == None
evaluates to false
Check if all values in series are equal where None == None
evaluates to true
.
Get a pointer to the underlying data of this Series. Can be useful for fast comparisons.
Methods from Deref<Target = dyn SeriesTrait>
Trait Implementations
Performs the conversion.
Apply a closure F
elementwise.
Apply a closure elementwise. The closure gets the index of the element as first argument.
Apply a closure elementwise. The closure gets the index of the element as first argument.
fn apply_cast_numeric<F, S>(&self, f: F) -> ChunkedArray<S> where
F: Fn(Series) -> S::Native + Copy,
S: PolarsNumericType,
fn apply_cast_numeric<F, S>(&self, f: F) -> ChunkedArray<S> where
F: Fn(Series) -> S::Native + Copy,
S: PolarsNumericType,
Apply a closure elementwise and cast to a Numeric ChunkedArray. This is fastest when the null check branching is more expensive than the closure application. Read more
fn branch_apply_cast_numeric_no_null<F, S>(&self, f: F) -> ChunkedArray<S> where
F: Fn(Option<Series>) -> S::Native + Copy,
S: PolarsNumericType,
fn branch_apply_cast_numeric_no_null<F, S>(&self, f: F) -> ChunkedArray<S> where
F: Fn(Option<Series>) -> S::Native + Copy,
S: PolarsNumericType,
Apply a closure on optional values and cast to Numeric ChunkedArray without null values.
Apply a closure elementwise including null values.
Create a boolean mask by checking for equality.
Create a boolean mask by checking for inequality.
Create a boolean mask by checking if self > rhs.
Create a boolean mask by checking if self >= rhs.
Create a boolean mask by checking if self < rhs.
Create a boolean mask by checking if self <= rhs.
Check for equality and regard missing values as equal.
Check for equality and regard missing values as equal.
Check for equality.
Check for inequality.
Greater than comparison.
Greater than or equal comparison.
Less than comparison.
Less than or equal comparison
Check for equality and regard missing values as equal.
Check for equality.
Check for inequality.
Greater than comparison.
Greater than or equal comparison.
Less than comparison.
Less than or equal comparison
Replace None values with a give value T
.
type Target = dyn SeriesTrait
type Target = dyn SeriesTrait
The resulting type after dereferencing.
Performs the conversion.
Performs the conversion.
Creates a value from an iterator. Read more
Creates a value from an iterator. Read more
Creates a value from an iterator. Read more
Creates a value from an iterator. Read more
Creates a value from an iterator. Read more
Creates a value from an iterator. Read more
Creates a value from an iterator. Read more
Creates a value from an iterator. Read more
Panics
Panics if Series have different lengths.
Creates a value from an iterator. Read more
Creates a value from an iterator. Read more
Creates a value from an iterator. Read more
Creates a value from an iterator. Read more
Creates a value from an iterator. Read more
Creates a value from an iterator. Read more
Creates a value from an iterator. Read more
Creates a value from an iterator. Read more
Checked integer division. Computes self / rhs, returning None if rhs == 0 or the division results in overflow.
Auto Trait Implementations
impl !RefUnwindSafe for Series
impl !UnwindSafe for Series
Blanket Implementations
Mutably borrows from an owned value. Read more