/**
* @dataProvider sumProvider
*/
public function testSum(DecimalValue $a, DecimalValue $b, $value)
{
$math = new DecimalMath();
$actual = $math->sum($a, $b);
$this->assertEquals($value, $actual->getValue());
$actual = $math->sum($b, $a);
$this->assertEquals($value, $actual->getValue());
}
/**
* Returns a QuantityValue representing the given amount, automatically assuming
* a level of uncertainty based on the digits given.
*
* The upper and lower bounds are determined automatically from the given
* digits by increasing resp. decreasing the least significant digit.
* E.g. "+0.01" would have upperBound "+0.02" and lowerBound "+0.01",
* while "-100" would have upperBound "-99" and lowerBound "-101".
*
* @param DecimalValue $amount The quantity
* @param string $unit The quantity's unit (use "1" for unit-less quantities)
* @param DecimalValue $margin
*
* @return QuantityValue
*/
private function newUncertainQuantityFromMargin(DecimalValue $amount, $unit = '1', DecimalValue $margin)
{
$decimalMath = new DecimalMath();
$margin = $margin->computeAbsolute();
$lowerBound = $decimalMath->sum($amount, $margin->computeComplement());
$upperBound = $decimalMath->sum($amount, $margin);
return new QuantityValue($amount, $unit, $upperBound, $lowerBound);
}
/**
* Returns a DecimalValue representing the symmetrical offset to be applied
* to the raw amount for a rough representation of the uncertainty interval,
* as in "amount +/- offset".
*
* The offset is calculated as max( amount - lowerBound, upperBound - amount ).
*
* @since 0.1
*
* @return DecimalValue
*/
public function getUncertaintyMargin()
{
$math = new DecimalMath();
$lowerMargin = $math->sum($this->getAmount(), $this->getLowerBound()->computeComplement());
$upperMargin = $math->sum($this->getUpperBound(), $this->getAmount()->computeComplement());
$margin = $math->max($lowerMargin, $upperMargin);
return $margin;
}
