/**
* Tests NumArray::dot with empty vectors
*/
public function testDotEmptyVectorVector()
{
$vector1 = NumPHP::zeros(0);
$vector2 = NumPHP::zeros(0);
$expectedNumArray = new NumArray(0);
$this->assertNumArrayEquals($expectedNumArray, $vector1->dot($vector2));
}
/**
* @param NumArray $matrix
* @param NumArray $vector
* @return NumArray
*/
protected static function backSubstitution(NumArray $matrix, NumArray $vector)
{
$shape = $matrix->getShape();
$xVector = \NumPHP\Core\NumPHP::zeros($shape[0]);
for ($i = $shape[0] - 1; $i >= 0; $i--) {
$sum = 0;
for ($j = $i + 1; $j < $shape[0]; $j++) {
$sum += $matrix->get($i, $j)->dot($xVector->get($j))->getData();
}
$xVector->set($i, ($vector->get($i)->getData() - $sum) / $matrix->get($i, $i)->getData());
}
return $xVector;
}
/**
* Tests NumArray::getSize on a 2x3x4 matrix
*/
public function getSize2x3x4()
{
$numArray = NumPHP::zeros(2, 3, 4);
$this->assertSame(24, $numArray->getSize());
}
/**
* Build the upper triangular matrix from given matrix
*
* @param NumArray $numArray given matrix
*
* @return NumArray
*
* @since 1.0.0
*/
protected static function buildUMatrix(NumArray $numArray)
{
$shape = $numArray->getShape();
$nAxis = $shape[1];
$size = min($shape[0], $nAxis);
$uMatrix = NumPHP::zeros($size, $nAxis);
for ($i = 0; $i < $size; $i++) {
$slice = sprintf("%d:", $i);
$uMatrix->set($i, $slice, $numArray->get($i, $slice));
}
return $uMatrix;
}
/**
* Tests NumArray::getShape on matrix size 2x4
*/
public function testGetShape2x4()
{
$numArray = NumPHP::zeros(2, 4);
$this->assertSame([2, 4], $numArray->getShape());
}
/**
* Tests NumPHP::zerosLike with 2x3 matrix
*/
public function testZerosLike()
{
$numArray = new NumArray([[1, 2, 3], [4, 5, 6]]);
$expectedNumArray = NumPHP::zeros(2, 3);
$this->assertNumArrayEquals($expectedNumArray, NumPHP::zerosLike($numArray));
}