FGCondition Class Reference

Detailed Description

Encapsulates a condition, which is used in parts of JSBSim including switches.

Definition at line 64 of file FGCondition.h.

#include <FGCondition.h>

Inheritance diagram for FGCondition:

Collaboration diagram for FGCondition:

Public Member Functions
	FGCondition (const std::string &test, std::shared_ptr< FGPropertyManager > PropertyManager, Element *el)
	FGCondition (Element *element, std::shared_ptr< FGPropertyManager > PropertyManager)
bool	Evaluate (void) const
void	PrintCondition (std::string indent=" ") const
Public Member Functions inherited from FGJSBBase
	FGJSBBase ()
	Constructor for FGJSBBase.
virtual	~FGJSBBase ()
	Destructor for FGJSBBase.
void	disableHighLighting (void)
	Disables highlighting in the console output.

Additional Inherited Members
Public Types inherited from FGJSBBase
enum	{ eL = 1 , eM , eN }
	Moments L, M, N. More...
enum	{ eP = 1 , eQ , eR }
	Rates P, Q, R. More...
enum	{ eU = 1 , eV , eW }
	Velocities U, V, W. More...
enum	{ eX = 1 , eY , eZ }
	Positions X, Y, Z. More...
enum	{ ePhi = 1 , eTht , ePsi }
	Euler angles Phi, Theta, Psi. More...
enum	{ eDrag = 1 , eSide , eLift }
	Stability axis forces, Drag, Side force, Lift. More...
enum	{ eRoll = 1 , ePitch , eYaw }
	Local frame orientation Roll, Pitch, Yaw. More...
enum	{ eNorth = 1 , eEast , eDown }
	Local frame position North, East, Down. More...
enum	{ eLat = 1 , eLong , eRad }
	Locations Radius, Latitude, Longitude. More...
enum	{   inNone = 0 , inDegrees , inRadians , inMeters ,   inFeet }
	Conversion specifiers. More...
Static Public Member Functions inherited from FGJSBBase
static const std::string &	GetVersion (void)
	Returns the version number of JSBSim.
static constexpr double	KelvinToFahrenheit (double kelvin)
	Converts from degrees Kelvin to degrees Fahrenheit.
static constexpr double	CelsiusToRankine (double celsius)
	Converts from degrees Celsius to degrees Rankine.
static constexpr double	RankineToCelsius (double rankine)
	Converts from degrees Rankine to degrees Celsius.
static constexpr double	KelvinToRankine (double kelvin)
	Converts from degrees Kelvin to degrees Rankine.
static constexpr double	RankineToKelvin (double rankine)
	Converts from degrees Rankine to degrees Kelvin.
static constexpr double	FahrenheitToCelsius (double fahrenheit)
	Converts from degrees Fahrenheit to degrees Celsius.
static constexpr double	CelsiusToFahrenheit (double celsius)
	Converts from degrees Celsius to degrees Fahrenheit.
static constexpr double	CelsiusToKelvin (double celsius)
	Converts from degrees Celsius to degrees Kelvin.
static constexpr double	KelvinToCelsius (double kelvin)
	Converts from degrees Kelvin to degrees Celsius.
static constexpr double	FeetToMeters (double measure)
	Converts from feet to meters.
static bool	EqualToRoundoff (double a, double b)
	Finite precision comparison.
static bool	EqualToRoundoff (float a, float b)
	Finite precision comparison.
static bool	EqualToRoundoff (float a, double b)
	Finite precision comparison.
static bool	EqualToRoundoff (double a, float b)
	Finite precision comparison.
static constexpr double	Constrain (double min, double value, double max)
	Constrain a value between a minimum and a maximum value.
static constexpr double	sign (double num)
Static Public Attributes inherited from FGJSBBase
static char	highint [5] = {27, '[', '1', 'm', '\0' }
	highlights text
static char	halfint [5] = {27, '[', '2', 'm', '\0' }
	low intensity text
static char	normint [6] = {27, '[', '2', '2', 'm', '\0' }
	normal intensity text
static char	reset [5] = {27, '[', '0', 'm', '\0' }
	resets text properties
static char	underon [5] = {27, '[', '4', 'm', '\0' }
	underlines text
static char	underoff [6] = {27, '[', '2', '4', 'm', '\0' }
	underline off
static char	fgblue [6] = {27, '[', '3', '4', 'm', '\0' }
	blue text
static char	fgcyan [6] = {27, '[', '3', '6', 'm', '\0' }
	cyan text
static char	fgred [6] = {27, '[', '3', '1', 'm', '\0' }
	red text
static char	fggreen [6] = {27, '[', '3', '2', 'm', '\0' }
	green text
static char	fgdef [6] = {27, '[', '3', '9', 'm', '\0' }
	default text
static short	debug_lvl = 1
Static Protected Member Functions inherited from FGJSBBase
static std::string	CreateIndexedPropertyName (const std::string &Property, int index)
Static Protected Attributes inherited from FGJSBBase
static constexpr double	radtodeg = 180. / M_PI
static constexpr double	degtorad = M_PI / 180.
static constexpr double	hptoftlbssec = 550.0
static constexpr double	psftoinhg = 0.014138
static constexpr double	psftopa = 47.88
static constexpr double	fttom = 0.3048
static constexpr double	ktstofps = 1852./(3600*fttom)
static constexpr double	fpstokts = 1.0 / ktstofps
static constexpr double	inchtoft = 1.0/12.0
static constexpr double	m3toft3 = 1.0/(fttom*fttom*fttom)
static constexpr double	in3tom3 = inchtoft*inchtoft*inchtoft/m3toft3
static constexpr double	inhgtopa = 3386.38
static constexpr double	slugtolb = 32.174049
	Note that definition of lbtoslug by the inverse of slugtolb and not to a different constant you can also get from some tables will make lbtoslug*slugtolb == 1 up to the magnitude of roundoff.
static constexpr double	lbtoslug = 1.0/slugtolb
static constexpr double	kgtolb = 2.20462
static constexpr double	kgtoslug = 0.06852168
static const std::string	needed_cfg_version = "2.0"
static const std::string	JSBSim_version = JSBSIM_VERSION " " __DATE__ " " __TIME__

Constructor & Destructor Documentation

FGCondition() [1/2]

FGCondition	(	Element *	element,
		std::shared_ptr< FGPropertyManager >	PropertyManager
	)

Definition at line 59 of file FGCondition.cpp.

  : Logic(elUndef), TestParam1(nullptr), TestParam2(nullptr),
    Comparison(ecUndef)
{
  string logic = element->GetAttributeValue("logic");
  if (!logic.empty()) {
    if (logic == "OR") Logic = eOR;
    else if (logic == "AND") Logic = eAND;
    else { // error
      throw BaseException("FGCondition: unrecognized LOGIC token:'" + logic + "'");
    }
  } else {
    Logic = eAND; // default
  }
 
  assert(Logic != elUndef);
 
  for (unsigned int i=0; i<element->GetNumDataLines(); i++) {
    string data = element->GetDataLine(i);
    conditions.push_back(make_shared<FGCondition>(data, PropertyManager, element));
  }
 
  Element* condition_element = element->GetElement();
  const string& elName = element->GetName();
 
  while (condition_element) {
    string tagName = condition_element->GetName();
 
    if (tagName != elName) {
      throw BaseException("FGCondition: unrecognized TAG:'" + tagName + "' in the condition statement.");
    }
 
    conditions.push_back(make_shared<FGCondition>(condition_element, PropertyManager));
    condition_element = element->GetNextElement();
  }
 
  if (conditions.empty()) throw BaseException("Empty conditional");
 
  Debug(0);
}

FGCondition() [2/2]

FGCondition	(	const std::string &	test,
		std::shared_ptr< FGPropertyManager >	PropertyManager,
		Element *	el
	)

Definition at line 104 of file FGCondition.cpp.

  : Logic(elUndef), TestParam1(nullptr), TestParam2(nullptr),
    Comparison(ecUndef)
{
  static constexpr array<pair<const char*, enum eComparison>, 18> mComparison {{
    {"!=", eNE},
    {"<",  eLT},
    {"<=", eLE},
    {"==", eEQ},
    {">",  eGT},
    {">=", eGE},
    {"EQ", eEQ},
    {"GE", eGE},
    {"GT", eGT},
    {"LE", eLE},
    {"LT", eLT},
    {"NE", eNE},
    {"eq", eEQ},
    {"ge", eGE},
    {"gt", eGT},
    {"le", eLE},
    {"lt", eLT},
    {"ne", eNE},
  }};
 
  vector<string> test_strings = split(test, ' ');
 
  if (test_strings.size() == 3) {
    TestParam1 = new FGPropertyValue(test_strings[0], PropertyManager, el);
    conditional = test_strings[1];
    TestParam2 = new FGParameterValue(test_strings[2], PropertyManager, el);
  } else {
    ostringstream s;
    s << "  Conditional test is invalid: \"" << test
      << "\" has " << test_strings.size() << " elements in the "
      << "test condition.\n";
    throw BaseException(s.str());
  }
 
  assert(Comparison == ecUndef);
  for(auto& elm: mComparison) {
    if (conditional == elm.first) {
      Comparison = elm.second;
      break;
    }
  }
 
  if (Comparison == ecUndef) {
    throw BaseException("FGCondition: Comparison operator: \""+conditional
          +"\" does not exist.  Please check the conditional.");
  }
}

Member Function Documentation

Evaluate()

bool Evaluate

(

void

)

const

Definition at line 160 of file FGCondition.cpp.

{
  bool pass = false;
 
  if (!TestParam1) {
 
    if (Logic == eAND) {
 
      pass = true;
      for (auto& cond: conditions) {
        if (!cond->Evaluate()) pass = false;
      }
 
    } else { // Logic must be eOR
 
      pass = false;
      for (auto& cond: conditions) {
        if (cond->Evaluate()) pass = true;
      }
 
    }
 
  } else {
    double value1 = TestParam1->GetValue();
    double value2 = TestParam2->GetValue();
 
    switch (Comparison) {
    case eEQ:
      pass = value1 == value2;
      break;
    case eNE:
      pass = value1 != value2;
      break;
    case eGT:
      pass = value1 > value2;
      break;
    case eGE:
      pass = value1 >= value2;
      break;
    case eLT:
      pass = value1 < value2;
      break;
    case eLE:
      pass = value1 <= value2;
      break;
    default:
     assert(false);  // Should not be reached
     break;
    }
  }
 
  return pass;
}

PrintCondition()

void PrintCondition

(

std::string

indent = "  "

)

const

Definition at line 216 of file FGCondition.cpp.

{
  string scratch;
 
  if (!conditions.empty()) {
 
    switch(Logic) {
    case (elUndef):
      scratch = " UNSET";
      cerr << "unset logic for test condition" << endl;
      break;
    case (eAND):
      scratch = indent + "if all of the following are true: {";
      break;
    case (eOR):
      scratch = indent + "if any of the following are true: {";
      break;
    default:
      scratch = " UNKNOWN";
      cerr << "Unknown logic for test condition" << endl;
    }
    cout << scratch << endl;
 
    for (auto& cond: conditions) {
      cond->PrintCondition(indent + "  ");
      cout << endl;
    }
 
    cout << indent << "}";
 
  } else {
    cout << indent << TestParam1->GetName() << " " << conditional
         << " " << TestParam2->GetName();
  }
}

---

The documentation for this class was generated from the following files:

• FGCondition.h
• FGCondition.cpp