public function testCanEvaluateLog()
{
$this->assertResult('log(-1)', new Complex(0, pi()));
$this->assertResult('log(x)', Complex::log($this->variables['x']));
}
/**
* Evaluate a FunctionNode
*
* Computes the value of a FunctionNode `f(x)`, where f is
* an elementary function recognized by StdMathLexer and StdMathParser.
*
* @see \MathParser\Lexer\StdMathLexer StdMathLexer
* @see \MathParser\StdMathParser StdMathParser
* @throws UnknownFunctionException if the function respresented by the
* FunctionNode is *not* recognized.
*
* @param FunctionNode $node AST to be evaluated
* @retval float
*/
public function visitFunctionNode(FunctionNode $node)
{
$z = $node->getOperand()->accept($this);
$a = $z->r();
$b = $z->i();
switch ($node->getName()) {
// Trigonometric functions
case 'sin':
return Complex::sin($z);
case 'cos':
return Complex::cos($z);
case 'tan':
return Complex::tan($z);
case 'cot':
return Complex::cot($z);
// Inverse trigonometric functions
// Inverse trigonometric functions
case 'arcsin':
return Complex::arcsin($z);
case 'arccos':
return Complex::arccos($z);
case 'arctan':
return Complex::arctan($z);
case 'arccot':
return Complex::arccot($z);
case 'sinh':
return Complex::sinh($z);
case 'cosh':
return Complex::cosh($z);
case 'tanh':
return Complex::tanh($z);
case 'coth':
return Complex::div(1, Complex::tanh($z));
case 'arsinh':
return Complex::arsinh($z);
case 'arcosh':
return Complex::arcosh($z);
case 'artanh':
return Complex::artanh($z);
case 'arcoth':
return Complex::div(1, Complex::artanh($z));
case 'exp':
return Complex::exp($z);
case 'log':
return Complex::log($z);
case 'lg':
return Complex::div(Complex::log($z), M_LN10);
case 'sqrt':
return Complex::sqrt($z);
case 'abs':
return new Complex($z->abs(), 0);
case 'arg':
return new Complex($z->arg(), 0);
case 're':
return new Complex($z->r(), 0);
case 'im':
return new Complex($z->i(), 0);
case 'conj':
return new Complex($z->r(), -$z->i());
default:
throw new UnknownFunctionException($node->getName());
}
return new FunctionNode($node->getName(), $inner);
}
public function testCanComputeTranscendentals()
{
$z = new Complex(1, 2);
$accuracy = 1.0E-9;
$this->assertEquals(new Complex(1.27201965, 0.7861513778), Complex::sqrt($z), 'sqrt', $accuracy);
$this->assertEquals(new Complex(3.165778513, 1.959601041), Complex::sin($z), 'sin', $accuracy);
$this->assertEquals(new Complex(2.032723007, -3.051897799), Complex::cos($z), 'cos', $accuracy);
$this->assertEquals(new Complex(0.03381282608, 1.014793616), Complex::tan($z), 'tan', $accuracy);
$this->assertEquals(new Complex(0.03279775553, -0.9843292265), Complex::cot($z), 'cot', $accuracy);
$this->assertEquals(new Complex(0.4270785864, 1.528570919), Complex::arcsin($z), 'arcsin', $accuracy);
$this->assertEquals(new Complex(1.14371774, -1.528570919), Complex::arccos($z), 'arccos', $accuracy);
$this->assertEquals(new Complex(1.338972522, 0.4023594781), Complex::arctan($z), 'arctan', $accuracy);
$this->assertEquals(new Complex(0.2318238045, -0.4023594781), Complex::arccot($z), 'arccot', $accuracy);
$this->assertEquals(new Complex(-1.131204384, 2.471726672), Complex::exp($z), 'exp', $accuracy);
$this->assertEquals(new Complex(0.8047189562, 1.107148718), Complex::log($z), 'log', $accuracy);
$this->assertEquals(new Complex(-0.489056259, 1.403119251), Complex::sinh($z), 'sinh', $accuracy);
$this->assertEquals(new Complex(-0.6421481247, 1.068607421), Complex::cosh($z), 'cosh', $accuracy);
$this->assertEquals(new Complex(1.166736257, -0.2434582012), Complex::tanh($z), 'tanh', $accuracy);
$this->assertEquals(new Complex(1.469351744, 1.063440024), Complex::arsinh($z), 'arsinh', $accuracy);
$this->assertEquals(new Complex(1.528570919, 1.14371774), Complex::arcosh($z), 'arcosh', $accuracy);
$this->assertEquals(new Complex(0.1732867951, 1.178097245), Complex::artanh($z), 'artanh', $accuracy);
}