public function testDivisionByZero()
{
$x = Rational::parse('1/2');
$y = Rational::parse('0');
$this->setExpectedException(DivisionByZeroException::class);
$z = Rational::div($x, $y);
}
/**
* string representation of a complex number
*
*
* @param mixed $z (Complex, or parsable to Complex)
* @retval string
*/
public function __toString()
{
// TODO: use Number:: helper functions.
$realAsRational = Rational::fromFloat($this->x);
if ($realAsRational->q <= 100) {
$real = "{$realAsRational}";
} else {
$real = sprintf('%f', $this->x);
}
$imagAsRational = Rational::fromFloat($this->y);
if ($imagAsRational->q <= 100) {
$imag = $imagAsRational->signed();
} else {
$imag = sprintf('%+f', $this->y);
}
if ($this->y == 0) {
return $real;
}
if ($this->x == 0) {
if ($this->y == 1) {
return 'i';
}
if ($this->y == -1) {
return '-i';
}
if ($imag[0] == '+') {
$imag = substr($imag, 1);
}
return "{$imag}i";
}
if ($this->y == 1) {
$imag = '+';
}
if ($this->y == -1) {
$imag = '-';
}
return "{$real}{$imag}i";
}
