Struct ndarray_stats::histogram::Grid
source · pub struct Grid<A: Ord> { /* private fields */ }
Expand description
A Grid
is a partition of a rectangular region of an n-dimensional
space—e.g. [a0, b0) × ⋯ × [an−1,
bn−1)—into a collection of rectangular n-dimensional bins.
The grid is fully determined by its 1-dimensional projections on the
coordinate axes. For example, this is a partition that can be represented
as a Grid
struct:
+---+-------+-+
| | | |
+---+-------+-+
| | | |
| | | |
| | | |
| | | |
+---+-------+-+
while the next one can’t:
+---+-------+-+
| | | |
| +-------+-+
| | |
| | |
| | |
| | |
+---+-------+-+
Example:
extern crate ndarray_stats;
extern crate ndarray;
extern crate noisy_float;
use ndarray::{Array, array};
use ndarray_stats::{HistogramExt,
histogram::{Histogram, Grid, GridBuilder,
Edges, Bins, strategies::Auto}};
use noisy_float::types::{N64, n64};
// 1-dimensional observations, as a (n_observations, 1) 2-d matrix
let observations = Array::from_shape_vec(
(12, 1),
vec![1, 4, 5, 2, 100, 20, 50, 65, 27, 40, 45, 23],
).unwrap();
// The optimal grid layout is inferred from the data,
// specifying a strategy (Auto in this case)
let grid = GridBuilder::<Auto<usize>>::from_array(&observations).build();
let expected_grid = Grid::from(vec![Bins::new(Edges::from(vec![1, 20, 39, 58, 77, 96, 115]))]);
assert_eq!(grid, expected_grid);
let histogram = observations.histogram(grid);
let histogram_matrix = histogram.counts();
// Bins are left inclusive, right exclusive!
let expected = array![4, 3, 3, 1, 0, 1];
assert_eq!(histogram_matrix, expected.into_dyn());
Implementations
sourceimpl<A: Ord> Grid<A>
impl<A: Ord> Grid<A>
sourceimpl<A: Ord + Clone> Grid<A>
impl<A: Ord + Clone> Grid<A>
sourcepub fn index(&self, index: &[usize]) -> Vec<Range<A>>
pub fn index(&self, index: &[usize]) -> Vec<Range<A>>
Given i=(i_0, ..., i_{n-1})
, an n
-dimensional index, it returns
I_{i_0}x...xI_{i_{n-1}}
, an n
-dimensional bin, where I_{i_j}
is
the i_j
-th interval on the j
-th projection of the grid on the coordinate axes.
Panics if at least one among (i_0, ..., i_{n-1})
is out of bounds on the respective
coordinate axis - i.e. if there exists j
such that i_j >= self.projections[j].len()
.
Trait Implementations
sourceimpl<A: Ord> From<Vec<Bins<A>, Global>> for Grid<A>
impl<A: Ord> From<Vec<Bins<A>, Global>> for Grid<A>
sourcefn from(projections: Vec<Bins<A>>) -> Self
fn from(projections: Vec<Bins<A>>) -> Self
Get a Grid
instance from a Vec<Bins<A>>
.
The i
-th element in Vec<Bins<A>>
represents the 1-dimensional
projection of the bin grid on the i
-th axis.
Alternatively, a Grid
can be built directly from data using a
GridBuilder
.