Matrix & Vector Products

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vdot

public static vdot($a, $b) : CArray

Return the dot product of two vectors.

vdot does not perform a matrix product, but flattens input arguments to 1-D vectors first. Consequently, it should only be used for vectors.

Parameters

CArray|Array $a Input array.

CArray|Array $b Input array.

Returns

CArray Dot product of $a and $b.

Examples

Example 1

$a = new CArray([[1, 4], [5, 6]]);
$b = new CArray([[4, 1], [2, 2]]);

echo CArray::vdot($a, $b);

30.0000

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matmul

public static matmul($a, $b) : CArray

Matrix product of two arrays.

Parameters

CArray|Array $a Input array.

CArray|Array $b Input array.

Returns

CArray The matrix product of the inputs. This is a scalar only when both $x1, $x2 are 1-d vectors.

Examples

Example 1

$a = new CArray([[1, 4], [5, 6]]);
$b = new CArray([[4, 1], [2, 2]]);

echo CArray::matmul($a, $b);

[[ 12   9 ]
 [ 32  17 ]]

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inner

public static inner($a, $b) : CArray

Inner product of two arrays.

Parameters

CArray|Array $a Input array.

CArray|Array $b Input array.

Returns

CArray Inner product of the input arrays.