Ones and Zeros Routines
identity
public static identity($n) : CArray
Return the identity array.
The identity array is a square array with ones on the main diagonal.
Parameters
CArray|Array
$n Number of rows (and columns) in $n x $n
output.
Returns
CArray
$n x $n
CArray with its main diagonal set to one, and all other elements 0.
Examples
Example 1
echo CArray::identity(4);
[[ 1. 0. 0. 0. ]
[ 0. 1. 0. 0. ]
[ 0. 0. 1. 0. ]
[ 0. 0. 0. 1. ]]
eye
public static eye($n, $m = NULL, $k = 0) : CArray
Return a 2-D array with ones on the diagonal and zeros elsewhere.
Parameters
CArray|Array
$n Number of rows in the output.
CArray|Array
$m Number of columns in the output. If NULL, defaults to $n
.
CArray|Array
$k Index of the diagonal: 0 (the default) refers to the main diagonal, a positive value refers to
an upper diagonal, and a negative value to a lower diagonal.
Returns
CArray
An array where all elements are equal to zero, except for the $k
-th diagonal, whose values are equal to one.
Examples
Example 1
echo CArray::eye(3, 3, 1);
[[ 0. 1. 0. ]
[ 0. 0. 1. ]
[ 0. 0. 0. ]]
ones
public static ones(array $shape) : CArray
Return a new CArray of given shape, filled with ones.
Parameters
Array
$shape Shape of the new array, e.g., [2, 3]
or [2]
.
Returns
CArray
CArray of ones with the given shape.
zeros
public static zeros(array $shape) : CArray
Return a new CArray of given shape, filled with zeros.
Parameters
Array
$shape Shape of the new array, e.g., [2, 3]
or [2]
.
Returns
CArray
CArray of zeros with the given shape.