Struct AsRecords 

pub struct AsRecords<'a, I, T> { /* private fields */ }

A wrapper around another iterator of record data and a history for that iterator’s data that iterates though each element in the iterator as a Record instead.

The main purpose of this representation is to allow manipulating one or more RecordContainers as iterators of Records then collect the iterator back into a RecordContainer so containers of Records with a shared history don’t have to store the history for each element but the richer Record API can be used for operations anyway.

use easy_ml::differentiation::{WengertList, Record, RecordTensor};
use easy_ml::tensors::Tensor;
use easy_ml::numeric::extra::Real;

let history = WengertList::new();
let A = RecordTensor::variables(
    &history,
    Tensor::from_fn([("r", 3), ("c", 2)], |[r, c]| ((5 * r) + c) as f32)
);
let B = RecordTensor::variables(
    &history,
    Tensor::from([("x", 6)], vec![ 0.2, 0.1, 0.5, 0.3, 0.7, 0.9 ])
);

fn power<T: Real+ Copy>(x: T, y: T) -> T {
    x.pow(y)
}

let result: RecordTensor<_, _, 2> = RecordTensor::from_iter(
    A.shape(),
    // iterators of records don't need to have matching shapes as long as the number
    // of elements matches the final shape
    A.iter_as_records().zip(B.iter_as_records()).map(|(x, y)| power(x, y))
).expect("result should have 6 elements");

Implementations

impl<'a, 'b, T, S, const D: usize> AsRecords<'a, TensorIterator<'b, (T, Index), RecordTensor<'a, T, S, D>, D>, T>

where T: Numeric + Primitive, S: TensorRef<(T, Index), D>,

AsRecords can be created from a RecordTensor to manipulate the data as an iterator of Records then streamed back into a RecordTensor with from_iter

See also: map, map_mut

use easy_ml::differentiation::{WengertList, Record, RecordTensor};
use easy_ml::tensors::Tensor;

let history = WengertList::new();
let X = RecordTensor::constants(
    Tensor::from_fn([("r", 2), ("c", 2)], |[r, c]| (r + c) as f32)
);
let y = Record::variable(1.0, &history);
let result = RecordTensor::from_iter(
    [("r", 2), ("c", 2)],
    // Here we create each variable z from the constant in X and the variable y.
    // If we just did X + 1.0 we'd still have only constants, and we can't do X + y
    // directly because those traits aren't implemented.
    X.iter_as_records().map(|x| x + y)
);
// we can unwrap here because we know the iterator still contains 4 elements and they all
// have the same WengertList so we can convert back to a RecordTensor (which is now
// variables instead of constants)
let Z = result.unwrap();
let Z_indexing = Z.index();
assert_eq!(1.0, Z_indexing.get([0, 0]).0);
assert_eq!(2.0, Z_indexing.get([0, 1]).0);
assert_eq!(3.0, Z_indexing.get([1, 1]).0);

pub fn from_tensor(tensor: &'b RecordTensor<'a, T, S, D>) -> Self

Given a record tensor returns an iterator of Records

use easy_ml::differentiation::{WengertList, Record, RecordTensor};
use easy_ml::differentiation::iterators::AsRecords;
use easy_ml::tensors::Tensor;

let history = WengertList::new();
let X = RecordTensor::variables(
    &history,
    Tensor::from_fn([("r", 2), ("c", 2)], |[r, c]| (r + c) as f32)
);
let iter = X.iter_as_records(); // shorthand helper method
let also_iter = AsRecords::from_tensor(&X);

impl<'a, 'b, T, S> AsRecords<'a, RowMajorIterator<'b, (T, Index), RecordMatrix<'a, T, S>>, T>

where T: Numeric + Primitive, S: MatrixRef<(T, Index)> + NoInteriorMutability,

AsRecords can be created from a RecordMatrix to manipulate the data as an iterator of Records then streamed back into a RecordMatrix with from_iter

See also: map, map_mut

use easy_ml::differentiation::{WengertList, Record, RecordMatrix};
use easy_ml::matrices::Matrix;

let history = WengertList::new();
let X = RecordMatrix::constants(
    Matrix::from_fn((2, 2), |(r, c)| (r + c) as f32)
);
let y = Record::variable(1.0, &history);
let result = RecordMatrix::from_iter(
    (2, 2),
    // Here we create each variable z from the constant in X and the variable y.
    // If we just did X + 1.0 we'd still have only constants, and we can't do X + y
    // directly because those traits aren't implemented.
    X.iter_row_major_as_records().map(|x| x + y)
);
// we can unwrap here because we know the iterator still contains 4 elements and they all
// have the same WengertList so we can convert back to a RecordMatrix (which is now
// variables instead of constants)
let Z = result.unwrap();
let Z_view = Z.view();
assert_eq!(1.0, Z_view.get(0, 0).0);
assert_eq!(2.0, Z_view.get(0, 1).0);
assert_eq!(3.0, Z_view.get(1, 1).0);

pub fn from_matrix_row_major(matrix: &'b RecordMatrix<'a, T, S>) -> Self

Given a record matrix returns a row major iterator of Records

use easy_ml::differentiation::{WengertList, Record, RecordMatrix};
use easy_ml::differentiation::iterators::AsRecords;
use easy_ml::matrices::Matrix;

let history = WengertList::new();
let X = RecordMatrix::variables(
    &history,
    Matrix::from_fn((2, 2), |(r, c)| (r + c) as f32)
);
let iter = X.iter_row_major_as_records(); // shorthand helper method
let also_iter = AsRecords::from_matrix_row_major(&X);

impl<'a, 'b, T, S> AsRecords<'a, ColumnMajorIterator<'b, (T, Index), RecordMatrix<'a, T, S>>, T>

where T: Numeric + Primitive, S: MatrixRef<(T, Index)> + NoInteriorMutability,

pub fn from_matrix_column_major(matrix: &'b RecordMatrix<'a, T, S>) -> Self

Given a record matrix returns a column major iterator of Records

impl<'a, I, T> AsRecords<'a, I, T>

where T: Numeric + Primitive, I: Iterator<Item = (T, Index)>,

pub fn from(history: Option<&'a WengertList<T>>, numbers: I) -> Self

Given the WengertList an iterator of record numbers are for, returns an iterator of Records

The inputs are not checked for validity. It is possible to pass in the wrong Wengert list here or even numbers with indexes that aren’t tracked on the WengertList.

Where possible, consider using from_tensor, from_matrix_row_major or from_matrix_column_major instead.

impl<'a, I, T> AsRecords<'a, I, T>

where T: Numeric + Primitive, I: Iterator<Item = (T, Index)> + Into<WithIndex<I>>,

pub fn with_index(self) -> WithIndex<AsRecords<'a, WithIndex<I>, T>>

An iterator of Records that is created from an iterator which can provide the index for each element can also be coverted to a WithIndex iterator and provide the index for each record.

WithIndex appears twice in the return type because the original iterator itself is wrapped in WithIndex to create an iterator that provides indexes, and AsRecords must also be wrapped in WithIndex to implement the iterator trait with indexes from the original iterator’s implementation.

use easy_ml::differentiation::{WengertList, Record, RecordTensor};
use easy_ml::tensors::Tensor;

let history = WengertList::new();
let X = RecordTensor::variables(
    &history,
    Tensor::from([("r", 2), ("c", 2)], vec![ 0.5, 1.5, 2.5, 3.5 ])
);
let Y = RecordTensor::from_iter(
    [("r", 2), ("c", 2)],
    // Most Easy ML matrix and tensor iterators implement Into<WithIndex<Self>>, so we can
    // call with_index after creating the iterator
    X.iter_as_records().with_index().map(|([r, c], x)| x + ((r + (2 * c)) as f32))
).unwrap(); // we can unwrap here because we know the iterator is still 4 elements
// so matches the shape and we added constants to each Record element so the history
// is still consistent
assert_eq!(
    Tensor::from([("r", 2), ("c", 2)], vec![ 0.5, 3.5, 3.5, 6.5 ]),
    Y.view().map(|(x, _)| x)
);

impl<'a, I, O, T> AsRecords<'a, I, T>

where T: Numeric + Primitive, I: Iterator<Item = (O, (T, Index))>,

pub fn from_with_index(history: Option<&'a WengertList<T>>, numbers: I) -> Self

Given the WengertList an iterator of indexes and record numbers are for, returns an iterator of indexes and Records

The inputs are not checked for validity. It is possible to pass in the wrong Wengert list here or even numbers with indexes that aren’t tracked on the WengertList.

Where possible, consider using with_index on an existing iterator instead.

Trait Implementations

impl<'a, I, T> ExactSizeIterator for AsRecords<'a, I, T>

where T: Numeric + Primitive, I: Iterator<Item = (T, Index)> + ExactSizeIterator,

fn len(&self) -> usize

Returns the exact remaining length of the iterator.

fn is_empty(&self) -> bool

🔬This is a nightly-only experimental API. (exact_size_is_empty)

Returns true if the iterator is empty.

impl<'a, I, T> From<AsRecords<'a, I, T>> for WithIndex<AsRecords<'a, WithIndex<I>, T>>

where T: Numeric + Primitive, I: Iterator<Item = (T, Index)> + Into<WithIndex<I>>,

fn from(iterator: AsRecords<'a, I, T>) -> Self

Converts to this type from the input type.

impl<'a, I, T> Iterator for AsRecords<'a, I, T>

where T: Numeric + Primitive, I: Iterator<Item = (T, Index)>,

AsRecords is an iterator of Records, merging the history together with each iterator element.

type Item = Record<'a, T>

The type of the elements being iterated over.

fn next(&mut self) -> Option<Self::Item>

Advances the iterator and returns the next value.

fn size_hint(&self) -> (usize, Option<usize>)

Returns the bounds on the remaining length of the iterator.

fn next_chunk<const N: usize>( &mut self, ) -> Result<[Self::Item; N], IntoIter<Self::Item, N>>

where Self: Sized,

🔬This is a nightly-only experimental API. (iter_next_chunk)

Advances the iterator and returns an array containing the next N values.

fn count(self) -> usize

where Self: Sized,

Consumes the iterator, counting the number of iterations and returning it.

fn last(self) -> Option<Self::Item>

where Self: Sized,

Consumes the iterator, returning the last element.

fn advance_by(&mut self, n: usize) -> Result<(), NonZero<usize>>

🔬This is a nightly-only experimental API. (iter_advance_by)

Advances the iterator by n elements.

fn nth(&mut self, n: usize) -> Option<Self::Item>

Returns the nth element of the iterator.

fn step_by(self, step: usize) -> StepBy<Self>

where Self: Sized,

Creates an iterator starting at the same point, but stepping by the given amount at each iteration.

fn chain<U>(self, other: U) -> Chain<Self, <U as IntoIterator>::IntoIter>

where Self: Sized, U: IntoIterator<Item = Self::Item>,

Takes two iterators and creates a new iterator over both in sequence.

fn zip<U>(self, other: U) -> Zip<Self, <U as IntoIterator>::IntoIter>

where Self: Sized, U: IntoIterator,

‘Zips up’ two iterators into a single iterator of pairs.

fn intersperse(self, separator: Self::Item) -> Intersperse<Self>

where Self: Sized, Self::Item: Clone,

🔬This is a nightly-only experimental API. (iter_intersperse)

Creates a new iterator which places a copy of separator between adjacent items of the original iterator.

fn intersperse_with<G>(self, separator: G) -> IntersperseWith<Self, G>

where Self: Sized, G: FnMut() -> Self::Item,

🔬This is a nightly-only experimental API. (iter_intersperse)

Creates a new iterator which places an item generated by separator between adjacent items of the original iterator.

fn map<B, F>(self, f: F) -> Map<Self, F>

where Self: Sized, F: FnMut(Self::Item) -> B,

Takes a closure and creates an iterator which calls that closure on each element.

fn for_each<F>(self, f: F)

where Self: Sized, F: FnMut(Self::Item),

Calls a closure on each element of an iterator.

fn filter<P>(self, predicate: P) -> Filter<Self, P>

where Self: Sized, P: FnMut(&Self::Item) -> bool,

Creates an iterator which uses a closure to determine if an element should be yielded.

fn filter_map<B, F>(self, f: F) -> FilterMap<Self, F>

where Self: Sized, F: FnMut(Self::Item) -> Option<B>,

Creates an iterator that both filters and maps.

fn enumerate(self) -> Enumerate<Self>

where Self: Sized,

Creates an iterator which gives the current iteration count as well as the next value.

fn peekable(self) -> Peekable<Self>

where Self: Sized,

Creates an iterator which can use the peek and peek_mut methods to look at the next element of the iterator without consuming it. See their documentation for more information.

fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P>

where Self: Sized, P: FnMut(&Self::Item) -> bool,

Creates an iterator that skips elements based on a predicate.

fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P>

where Self: Sized, P: FnMut(&Self::Item) -> bool,

Creates an iterator that yields elements based on a predicate.

fn map_while<B, P>(self, predicate: P) -> MapWhile<Self, P>

where Self: Sized, P: FnMut(Self::Item) -> Option<B>,

Creates an iterator that both yields elements based on a predicate and maps.

fn skip(self, n: usize) -> Skip<Self>

where Self: Sized,

Creates an iterator that skips the first n elements.

fn take(self, n: usize) -> Take<Self>

where Self: Sized,

Creates an iterator that yields the first n elements, or fewer if the underlying iterator ends sooner.

fn scan<St, B, F>(self, initial_state: St, f: F) -> Scan<Self, St, F>

where Self: Sized, F: FnMut(&mut St, Self::Item) -> Option<B>,

An iterator adapter which, like fold, holds internal state, but unlike fold, produces a new iterator.

fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F>

where Self: Sized, U: IntoIterator, F: FnMut(Self::Item) -> U,

Creates an iterator that works like map, but flattens nested structure.

fn map_windows<F, R, const N: usize>(self, f: F) -> MapWindows<Self, F, N>

where Self: Sized, F: FnMut(&[Self::Item; N]) -> R,

🔬This is a nightly-only experimental API. (iter_map_windows)

Calls the given function f for each contiguous window of size N over self and returns an iterator over the outputs of f. Like slice::windows(), the windows during mapping overlap as well.

fn fuse(self) -> Fuse<Self>

where Self: Sized,

Creates an iterator which ends after the first None.

fn inspect<F>(self, f: F) -> Inspect<Self, F>

where Self: Sized, F: FnMut(&Self::Item),

Does something with each element of an iterator, passing the value on.

fn by_ref(&mut self) -> &mut Self

where Self: Sized,

Creates a “by reference” adapter for this instance of Iterator.

fn collect<B>(self) -> B

where B: FromIterator<Self::Item>, Self: Sized,

Transforms an iterator into a collection.

fn collect_into<E>(self, collection: &mut E) -> &mut E

where E: Extend<Self::Item>, Self: Sized,

🔬This is a nightly-only experimental API. (iter_collect_into)

Collects all the items from an iterator into a collection.

fn partition<B, F>(self, f: F) -> (B, B)

where Self: Sized, B: Default + Extend<Self::Item>, F: FnMut(&Self::Item) -> bool,

Consumes an iterator, creating two collections from it.

fn is_partitioned<P>(self, predicate: P) -> bool

where Self: Sized, P: FnMut(Self::Item) -> bool,

🔬This is a nightly-only experimental API. (iter_is_partitioned)

Checks if the elements of this iterator are partitioned according to the given predicate, such that all those that return true precede all those that return false.

fn try_fold<B, F, R>(&mut self, init: B, f: F) -> R

where Self: Sized, F: FnMut(B, Self::Item) -> R, R: Try<Output = B>,

An iterator method that applies a function as long as it returns successfully, producing a single, final value.

fn try_for_each<F, R>(&mut self, f: F) -> R

where Self: Sized, F: FnMut(Self::Item) -> R, R: Try<Output = ()>,

An iterator method that applies a fallible function to each item in the iterator, stopping at the first error and returning that error.

fn fold<B, F>(self, init: B, f: F) -> B

where Self: Sized, F: FnMut(B, Self::Item) -> B,

Folds every element into an accumulator by applying an operation, returning the final result.

fn reduce<F>(self, f: F) -> Option<Self::Item>

where Self: Sized, F: FnMut(Self::Item, Self::Item) -> Self::Item,

Reduces the elements to a single one, by repeatedly applying a reducing operation.

fn try_reduce<R>( &mut self, f: impl FnMut(Self::Item, Self::Item) -> R, ) -> <<R as Try>::Residual as Residual<Option<<R as Try>::Output>>>::TryType

where Self: Sized, R: Try<Output = Self::Item>, <R as Try>::Residual: Residual<Option<Self::Item>>,

🔬This is a nightly-only experimental API. (iterator_try_reduce)

Reduces the elements to a single one by repeatedly applying a reducing operation. If the closure returns a failure, the failure is propagated back to the caller immediately.

fn all<F>(&mut self, f: F) -> bool

where Self: Sized, F: FnMut(Self::Item) -> bool,

Tests if every element of the iterator matches a predicate.

fn any<F>(&mut self, f: F) -> bool

where Self: Sized, F: FnMut(Self::Item) -> bool,

Tests if any element of the iterator matches a predicate.

fn find<P>(&mut self, predicate: P) -> Option<Self::Item>

where Self: Sized, P: FnMut(&Self::Item) -> bool,

Searches for an element of an iterator that satisfies a predicate.

fn find_map<B, F>(&mut self, f: F) -> Option<B>

where Self: Sized, F: FnMut(Self::Item) -> Option<B>,

Applies function to the elements of iterator and returns the first non-none result.

fn try_find<R>( &mut self, f: impl FnMut(&Self::Item) -> R, ) -> <<R as Try>::Residual as Residual<Option<Self::Item>>>::TryType

where Self: Sized, R: Try<Output = bool>, <R as Try>::Residual: Residual<Option<Self::Item>>,

🔬This is a nightly-only experimental API. (try_find)

Applies function to the elements of iterator and returns the first true result or the first error.

fn position<P>(&mut self, predicate: P) -> Option<usize>

where Self: Sized, P: FnMut(Self::Item) -> bool,

Searches for an element in an iterator, returning its index.

fn max_by_key<B, F>(self, f: F) -> Option<Self::Item>

where B: Ord, Self: Sized, F: FnMut(&Self::Item) -> B,

Returns the element that gives the maximum value from the specified function.

fn max_by<F>(self, compare: F) -> Option<Self::Item>

where Self: Sized, F: FnMut(&Self::Item, &Self::Item) -> Ordering,

Returns the element that gives the maximum value with respect to the specified comparison function.

fn min_by_key<B, F>(self, f: F) -> Option<Self::Item>

where B: Ord, Self: Sized, F: FnMut(&Self::Item) -> B,

Returns the element that gives the minimum value from the specified function.

fn min_by<F>(self, compare: F) -> Option<Self::Item>

where Self: Sized, F: FnMut(&Self::Item, &Self::Item) -> Ordering,

Returns the element that gives the minimum value with respect to the specified comparison function.

fn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB)

where FromA: Default + Extend<A>, FromB: Default + Extend<B>, Self: Sized + Iterator<Item = (A, B)>,

Converts an iterator of pairs into a pair of containers.

fn copied<'a, T>(self) -> Copied<Self>

where T: Copy + 'a, Self: Sized + Iterator<Item = &'a T>,

Creates an iterator which copies all of its elements.

fn cloned<'a, T>(self) -> Cloned<Self>

where T: Clone + 'a, Self: Sized + Iterator<Item = &'a T>,

Creates an iterator which clones all of its elements.

fn array_chunks<const N: usize>(self) -> ArrayChunks<Self, N>

where Self: Sized,

🔬This is a nightly-only experimental API. (iter_array_chunks)

Returns an iterator over N elements of the iterator at a time.

fn sum<S>(self) -> S

where Self: Sized, S: Sum<Self::Item>,

Sums the elements of an iterator.

fn product<P>(self) -> P

where Self: Sized, P: Product<Self::Item>,

Iterates over the entire iterator, multiplying all the elements

fn cmp_by<I, F>(self, other: I, cmp: F) -> Ordering

where Self: Sized, I: IntoIterator, F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Ordering,

🔬This is a nightly-only experimental API. (iter_order_by)

Lexicographically compares the elements of this Iterator with those of another with respect to the specified comparison function.

fn partial_cmp<I>(self, other: I) -> Option<Ordering>

where I: IntoIterator, Self::Item: PartialOrd<<I as IntoIterator>::Item>, Self: Sized,

Lexicographically compares the PartialOrd elements of this Iterator with those of another. The comparison works like short-circuit evaluation, returning a result without comparing the remaining elements. As soon as an order can be determined, the evaluation stops and a result is returned.

fn partial_cmp_by<I, F>(self, other: I, partial_cmp: F) -> Option<Ordering>

where Self: Sized, I: IntoIterator, F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Option<Ordering>,

🔬This is a nightly-only experimental API. (iter_order_by)

Lexicographically compares the elements of this Iterator with those of another with respect to the specified comparison function.

fn eq<I>(self, other: I) -> bool

where I: IntoIterator, Self::Item: PartialEq<<I as IntoIterator>::Item>, Self: Sized,

Determines if the elements of this Iterator are equal to those of another.

fn eq_by<I, F>(self, other: I, eq: F) -> bool

where Self: Sized, I: IntoIterator, F: FnMut(Self::Item, <I as IntoIterator>::Item) -> bool,

🔬This is a nightly-only experimental API. (iter_order_by)

Determines if the elements of this Iterator are equal to those of another with respect to the specified equality function.

fn ne<I>(self, other: I) -> bool

where I: IntoIterator, Self::Item: PartialEq<<I as IntoIterator>::Item>, Self: Sized,

Determines if the elements of this Iterator are not equal to those of another.

fn lt<I>(self, other: I) -> bool

where I: IntoIterator, Self::Item: PartialOrd<<I as IntoIterator>::Item>, Self: Sized,

Determines if the elements of this Iterator are lexicographically less than those of another.

fn le<I>(self, other: I) -> bool

where I: IntoIterator, Self::Item: PartialOrd<<I as IntoIterator>::Item>, Self: Sized,

Determines if the elements of this Iterator are lexicographically less or equal to those of another.

fn gt<I>(self, other: I) -> bool

where I: IntoIterator, Self::Item: PartialOrd<<I as IntoIterator>::Item>, Self: Sized,

Determines if the elements of this Iterator are lexicographically greater than those of another.

fn ge<I>(self, other: I) -> bool

where I: IntoIterator, Self::Item: PartialOrd<<I as IntoIterator>::Item>, Self: Sized,

Determines if the elements of this Iterator are lexicographically greater than or equal to those of another.

fn is_sorted(self) -> bool

where Self: Sized, Self::Item: PartialOrd,

Checks if the elements of this iterator are sorted.

fn is_sorted_by<F>(self, compare: F) -> bool

where Self: Sized, F: FnMut(&Self::Item, &Self::Item) -> bool,

Checks if the elements of this iterator are sorted using the given comparator function.

fn is_sorted_by_key<F, K>(self, f: F) -> bool

where Self: Sized, F: FnMut(Self::Item) -> K, K: PartialOrd,

Checks if the elements of this iterator are sorted using the given key extraction function.

impl<'a, I, T> FusedIterator for AsRecords<'a, I, T>

where T: Numeric + Primitive, I: Iterator<Item = (T, Index)> + FusedIterator,