ndarray/
impl_2d.rs

1// Copyright 2014-2016 bluss and ndarray developers.
2//
3// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
4// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
5// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
6// option. This file may not be copied, modified, or distributed
7// except according to those terms.
8
9//! Methods for two-dimensional arrays.
10use crate::imp_prelude::*;
11
12/// # Methods For 2-D Arrays
13impl<A, S> ArrayBase<S, Ix2>
14where
15    S: RawData<Elem = A>,
16{
17    /// Return an array view of row `index`.
18    ///
19    /// **Panics** if `index` is out of bounds.
20    ///
21    /// ```
22    /// use ndarray::array;
23    /// let array = array![[1., 2.], [3., 4.]];
24    /// assert_eq!(array.row(0), array![1., 2.]);
25    /// ```
26    pub fn row(&self, index: Ix) -> ArrayView1<'_, A>
27    where
28        S: Data,
29    {
30        self.index_axis(Axis(0), index)
31    }
32
33    /// Return a mutable array view of row `index`.
34    ///
35    /// **Panics** if `index` is out of bounds.
36    ///
37    /// ```
38    /// use ndarray::array;
39    /// let mut array = array![[1., 2.], [3., 4.]];
40    /// array.row_mut(0)[1] = 5.;
41    /// assert_eq!(array, array![[1., 5.], [3., 4.]]);
42    /// ```
43    pub fn row_mut(&mut self, index: Ix) -> ArrayViewMut1<'_, A>
44    where
45        S: DataMut,
46    {
47        self.index_axis_mut(Axis(0), index)
48    }
49
50    /// Return the number of rows (length of `Axis(0)`) in the two-dimensional array.
51    ///
52    /// ```
53    /// use ndarray::array;
54    /// let array = array![[1., 2.], [3., 4.]];
55    /// assert_eq!(array.nrows(), 2usize);
56    /// ```
57    pub fn nrows(&self) -> usize {
58        self.len_of(Axis(0))
59    }
60
61    /// Return an array view of column `index`.
62    ///
63    /// **Panics** if `index` is out of bounds.
64    ///
65    /// ```
66    /// use ndarray::array;
67    /// let array = array![[1., 2.], [3., 4.]];
68    /// assert_eq!(array.column(0), array![1., 3.]);
69    /// ```
70    pub fn column(&self, index: Ix) -> ArrayView1<'_, A>
71    where
72        S: Data,
73    {
74        self.index_axis(Axis(1), index)
75    }
76
77    /// Return a mutable array view of column `index`.
78    ///
79    /// **Panics** if `index` is out of bounds.
80    ///
81    /// ```
82    /// use ndarray::array;
83    /// let mut array = array![[1., 2.], [3., 4.]];
84    /// array.column_mut(0)[1] = 5.;
85    /// assert_eq!(array, array![[1., 2.], [5., 4.]]);
86    /// ```
87    pub fn column_mut(&mut self, index: Ix) -> ArrayViewMut1<'_, A>
88    where
89        S: DataMut,
90    {
91        self.index_axis_mut(Axis(1), index)
92    }
93
94    /// Return the number of columns (length of `Axis(1)`) in the two-dimensional array.
95    ///
96    /// ```
97    /// use ndarray::array;
98    /// let array = array![[1., 2.], [3., 4.]];
99    /// assert_eq!(array.ncols(), 2usize);
100    /// ```
101    pub fn ncols(&self) -> usize {
102        self.len_of(Axis(1))
103    }
104
105    /// Return true if the array is square, false otherwise.
106    ///
107    /// # Examples
108    /// Sqaure:
109    /// ```
110    /// use ndarray::array;
111    /// let array = array![[1., 2.], [3., 4.]];
112    /// assert!(array.is_square());
113    /// ```
114    /// Not sqaure:
115    /// ```
116    /// use ndarray::array;
117    /// let array = array![[1., 2., 5.], [3., 4., 6.]];
118    /// assert!(!array.is_square());
119    /// ```
120    pub fn is_square(&self) -> bool {
121        let (m, n) = self.dim();
122        m == n
123    }
124}
ndarray/impl_2d.rs

ndarray/
impl_2d.rs
