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<?php

namespace PhpOffice\PhpSpreadsheet\Calculation\Engineering;

use PhpOffice\PhpSpreadsheet\Calculation\ArrayEnabled;

use PhpOffice\PhpSpreadsheet\Calculation\Exception;

use PhpOffice\PhpSpreadsheet\Calculation\Information\ExcelError;

class BesselY

{

    use ArrayEnabled;

    /**

     * BESSELY.

     *

     * Returns the Bessel function, which is also called the Weber function or the Neumann function.

     *

     *    Excel Function:

     *        BESSELY(x,ord)

     *

     * @param mixed $x A float value at which to evaluate the function.

     *                   If x is nonnumeric, BESSELY returns the #VALUE! error value.

     *                      Or can be an array of values

     * @param mixed $ord The integer order of the Bessel function.

     *                       If ord is not an integer, it is truncated.

     *                       If $ord is nonnumeric, BESSELY returns the #VALUE! error value.

     *                       If $ord < 0, BESSELY returns the #NUM! error value.

     *                      Or can be an array of values

     *

     * @return array|float|string Result, or a string containing an error

     *         If an array of numbers is passed as an argument, then the returned result will also be an array

     *            with the same dimensions

     */

    public static function BESSELY(mixed $x, mixed $ord): array|string|float

    {

        if (is_array($x) || is_array($ord)) {

            return self::evaluateArrayArguments([self::class, __FUNCTION__], $x, $ord);

        }

        try {

            $x = EngineeringValidations::validateFloat($x);

            $ord = EngineeringValidations::validateInt($ord);

        } catch (Exception $e) {

            return $e->getMessage();

        }

        if (($ord < 0) || ($x <= 0.0)) {

            return ExcelError::NAN();

        }

        $fBy = self::calculate($x, $ord);

        return (is_nan($fBy)) ? ExcelError::NAN() : $fBy;

    }

    private static function calculate(float $x, int $ord): float

    {

        return match ($ord) {

            1 => self::besselY1($x),

            default => self::besselY2($x, $ord),

        };

    }

    /**

     * Mollify Phpstan.

     *

     * @codeCoverageIgnore

     */

    private static function callBesselJ(float $x, int $ord): float

    {

        $rslt = BesselJ::BESSELJ($x, $ord);

        if (!is_float($rslt)) {

            throw new Exception('Unexpected array or string');

        }

        return $rslt;

    }

    private static function besselY0(float $x): float

    {

        if ($x < 8.0) {

            $y = ($x * $x);

            $ans1 = -2957821389.0 + $y * (7062834065.0 + $y * (-512359803.6 + $y * (10879881.29 + $y

                            * (-86327.92757 + $y * 228.4622733))));

            $ans2 = 40076544269.0 + $y * (745249964.8 + $y * (7189466.438 + $y

                        * (47447.26470 + $y * (226.1030244 + $y))));

            return $ans1 / $ans2 + 0.636619772 * self::callBesselJ($x, 0) * log($x);

        }

        $z = 8.0 / $x;

        $y = ($z * $z);

        $xx = $x - 0.785398164;

        $ans1 = 1 + $y * (-0.1098628627e-2 + $y * (0.2734510407e-4 + $y * (-0.2073370639e-5 + $y * 0.2093887211e-6)));

        $ans2 = -0.1562499995e-1 + $y * (0.1430488765e-3 + $y * (-0.6911147651e-5 + $y * (0.7621095161e-6 + $y

                        * (-0.934945152e-7))));

        return sqrt(0.636619772 / $x) * (sin($xx) * $ans1 + $z * cos($xx) * $ans2);

    }

    private static function besselY1(float $x): float

    {

        if ($x < 8.0) {

            $y = ($x * $x);

            $ans1 = $x * (-0.4900604943e13 + $y * (0.1275274390e13 + $y * (-0.5153438139e11 + $y

                            * (0.7349264551e9 + $y * (-0.4237922726e7 + $y * 0.8511937935e4)))));

            $ans2 = 0.2499580570e14 + $y * (0.4244419664e12 + $y * (0.3733650367e10 + $y * (0.2245904002e8 + $y

                            * (0.1020426050e6 + $y * (0.3549632885e3 + $y)))));

            return ($ans1 / $ans2) + 0.636619772 * (self::callBesselJ($x, 1) * log($x) - 1 / $x);

        }

        $z = 8.0 / $x;

        $y = $z * $z;

        $xx = $x - 2.356194491;

        $ans1 = 1.0 + $y * (0.183105e-2 + $y * (-0.3516396496e-4 + $y * (0.2457520174e-5 + $y * (-0.240337019e-6))));

        $ans2 = 0.04687499995 + $y * (-0.2002690873e-3 + $y * (0.8449199096e-5 + $y

                    * (-0.88228987e-6 + $y * 0.105787412e-6)));

        return sqrt(0.636619772 / $x) * (sin($xx) * $ans1 + $z * cos($xx) * $ans2);

    }

    private static function besselY2(float $x, int $ord): float

    {

        $fTox = 2.0 / $x;

        $fBym = self::besselY0($x);

        $fBy = self::besselY1($x);

        for ($n = 1; $n < $ord; ++$n) {

            $fByp = $n * $fTox * $fBy - $fBym;

            $fBym = $fBy;

            $fBy = $fByp;

        }

        return $fBy;

    }

}