Error in -1² operation when zero in imaginary part is represented in scientific notation

[josecelano]

Basically pow function does not work when Complex is instantiated using this notation 0E-42 for zero.

For exmaple:

$c2 = Complex::fromStringNumber('-1.0000000000000000000000000000', '0E-42');

You get that representation of zero internally, for example after another operation like: -0² - 1

I have added a test to reproduce the problem:

    /** @test */
    public function work_using_zero_with_scientific_notation_but_it_does_not_for_some_cases() {
        $_1 = Complex::fromInt(1, 0);

        $zero = new Decimal('0E-42');
        $this->assertTrue($zero->isZero());

        // Different ways to represent number 1 real. = imaginary part in scientific notation
        $c1 = Complex::fromStringNumber('-1.000000000000000000000000000000', '0E-84');  // 0 * 10^⁻84
        $c2 = Complex::fromStringNumber('-1.0000000000000000000000000000', '0E-42');    // 0 * 10^⁻42

        // 1² = 1
        $f1 = $c1->pow(2);
        $f2 = $c2->pow(2);

        $this->assertEqualWithDelta($_1, $f1);
        $this->assertEqualWithDelta($_1, $f2);
    }