KDL::JntArray Class Reference

#include <src/jntarray.hpp>

Public Member Functions
	JntArray ()
	Construct with no data array.
	JntArray (unsigned int size)
	Constructor of the joint array.
	JntArray (const JntArray &arg)
	Copy constructor.
	~JntArray ()
void	resize (unsigned int newSize)
	Resize the array.
JntArray &	operator= (const JntArray &arg)
double	operator() (unsigned int i, unsigned int j=0) const
	get_item operator for the joint array, if a second value is given it should be zero, since a JntArray resembles a column.
double &	operator() (unsigned int i, unsigned int j=0)
	set_item operator, again if a second value is given it should be zero.
unsigned int	rows () const
	Returns the number of rows (size) of the array.
unsigned int	columns () const
	Returns the number of columns of the array, always 1.

Public Attributes
Eigen::VectorXd	data

Friends
void	Add (const JntArray &src1, const JntArray &src2, JntArray &dest)
	Function to add two joint arrays, all the arguments must have the same size: A + B = C.
void	Subtract (const JntArray &src1, const JntArray &src2, JntArray &dest)
	Function to subtract two joint arrays, all the arguments must have the same size: A - B = C.
void	Multiply (const JntArray &src, const double &factor, JntArray &dest)
	Function to multiply all the array values with a scalar factor: A*b=C.
void	Divide (const JntArray &src, const double &factor, JntArray &dest)
	Function to divide all the array values with a scalar factor: A/b=C.
void	MultiplyJacobian (const Jacobian &jac, const JntArray &src, Twist &dest)
	Function to multiply a KDL::Jacobian with a KDL::JntArray to get a KDL::Twist, it should not be used to calculate the forward velocity kinematics, the solver classes are built for this purpose.
void	SetToZero (JntArray &array)
	Function to set all the values of the array to 0.
bool	Equal (const JntArray &src1, const JntArray &src2, double eps=epsilon)
	Function to check if two arrays are the same with a precision of eps.
bool	operator== (const JntArray &src1, const JntArray &src2)

Detailed Description

  @brief This class represents an fixed size array containing
  joint values of a KDL::Chain.

  \warning An object constructed with the default constructor provides
  a valid, but inert, object. Many of the member functions will do
  the correct thing and have no affect on this object, but some 
  member functions can _NOT_ deal with an inert/empty object. These 
  functions will assert() and exit the program instead. The intended use 
  case for the default constructor (in an RTT/OCL setting) is outlined in
  code below - the default constructor plus the resize() function allow
  use of JntArray objects whose size is set within a configureHook() call
  (typically based on a size determined from a property).

class MyTask : public RTT::TaskContext
{
   JntArray             j;
   MyTask() 
   {}                   // invokes j's default constructor
 
   bool configureHook()
   {
       unsigned int size = some_property.rvalue();
           j.resize(size)
           ...
   }
 
   void updateHook()
   {
      use j here
   }
};

Constructor & Destructor Documentation

JntArray() [1/3]

KDL::JntArray::JntArray

(

)

Construct with no data array.

Postcondition

NULL == data

0 == rows()

Warning

use of an object constructed like this, without a resize() first, may result in program exit! See class documentation.

Referenced by Add, Divide, Equal, JntArray(), Multiply, MultiplyJacobian, operator=(), operator==, SetToZero, and Subtract.

JntArray() [2/3]

KDL::JntArray::JntArray ( unsigned int size )

explicit

Constructor of the joint array.

Parameters

size	size of the array, this cannot be changed afterwards.

Precondition

0 < size

Postcondition

NULL != data

0 < rows()

all elements in data have 0 value

References data.

JntArray() [3/3]

KDL::JntArray::JntArray

(

const JntArray &

arg

)

Copy constructor.

Note

Will correctly copy an empty object

References data, and JntArray().

~JntArray()

KDL::JntArray::~JntArray

(

)

Member Function Documentation

columns()

unsigned int KDL::JntArray::columns

(

)

const

Returns the number of columns of the array, always 1.

References data.

operator()() [1/2]

double & KDL::JntArray::operator()	(	unsigned int	i,
		unsigned int	j = 0 )

set_item operator, again if a second value is given it should be zero.

Returns

reference to the joint value at position i,starting from zero.

Precondition

0 != size (ie non-default constructor or resize() called)

References data.

operator()() [2/2]

double KDL::JntArray::operator()	(	unsigned int	i,
		unsigned int	j = 0 ) const

get_item operator for the joint array, if a second value is given it should be zero, since a JntArray resembles a column.

Returns

the joint value at position i, starting from 0

Precondition

0 != size (ie non-default constructor or resize() called)

References data.

operator=()

JntArray & KDL::JntArray::operator=

(

const JntArray &

arg

)

References data, and JntArray().

resize()

void KDL::JntArray::resize

(

unsigned int

newSize

)

Resize the array.

Warning

This causes a dynamic allocation (and potentially
also a dynamic deallocation). This will negatively affect real-time performance!

Postcondition

newSize == rows()

NULL != data

all elements in data have 0 value

References data.

rows()

unsigned int KDL::JntArray::rows

(

)

const

Returns the number of rows (size) of the array.

References data.

Referenced by KDL::ChainFdSolver_RNE::CartToJnt(), KDL::ChainHdSolver_Vereshchagin::CartToJnt(), KDL::ChainIdSolver_RNE::CartToJnt(), KDL::ChainIkSolverPos_LMA::CartToJnt(), KDL::ChainIkSolverPos_NR::CartToJnt(), KDL::ChainIkSolverPos_NR_JL::CartToJnt(), KDL::ChainIkSolverVel_pinv::CartToJnt(), KDL::ChainIkSolverVel_pinv_givens::CartToJnt(), KDL::ChainIkSolverVel_pinv_nso::CartToJnt(), KDL::ChainIkSolverVel_wdls::CartToJnt(), KDL::TreeIdSolver_RNE::CartToJnt(), KDL::TreeIkSolverPos_Online::CartToJnt(), KDL::TreeIkSolverVel_wdls::CartToJnt(), Equal, KDL::ChainExternalWrenchEstimator::getEstimatedJntTorque(), KDL::ChainFkSolverPos_recursive::JntToCart(), KDL::ChainFkSolverPos_recursive::JntToCart(), KDL::ChainFkSolverVel_recursive::JntToCart(), KDL::ChainFkSolverVel_recursive::JntToCart(), KDL::TreeFkSolverPos_recursive::JntToCart(), KDL::ChainExternalWrenchEstimator::JntToExtWrench(), KDL::ChainJntToJacSolver::JntToJac(), KDL::TreeJntToJacSolver::JntToJac(), KDL::ChainJntToJacDotSolver::JntToJacDot(), KDL::ChainDynParam::JntToMass(), KDL::operator<<(), KDL::ChainExternalWrenchEstimator::setInitialMomentum(), KDL::ChainIkSolverPos_NR_JL::setJointLimits(), KDL::ChainIkSolverVel_pinv_nso::setOptPos(), and KDL::ChainIkSolverVel_pinv_nso::setWeights().

Friends And Related Symbol Documentation

Add

void Add ( const JntArray & src1, const JntArray & src2, JntArray & dest )

friend

Function to add two joint arrays, all the arguments must have the same size: A + B = C.

This function is aliasing-safe, A or B can be the same array as C.

Parameters

src1	A
src2	B
dest	C

References data, and JntArray().

Divide

void Divide ( const JntArray & src, const double & factor, JntArray & dest )

friend

Function to divide all the array values with a scalar factor: A/b=C.

This function is aliasing-safe, A can be the same array as C.

Parameters

src	A
factor	b
dest	C

References data, and JntArray().

Equal

bool Equal ( const JntArray & src1, const JntArray & src2, double eps = epsilon )

friend

Function to check if two arrays are the same with a precision of eps.

Parameters

src1
src2
eps	default: epsilon

Returns

true if each element of src1 is within eps of the same element in src2, or if both src1 and src2 have no data (ie 0==rows())

References data, JntArray(), and rows().

Multiply

void Multiply ( const JntArray & src, const double & factor, JntArray & dest )

friend

Function to multiply all the array values with a scalar factor: A*b=C.

This function is aliasing-safe, A can be the same array as C.

Parameters

src	A
factor	b
dest	C

References data, and JntArray().

MultiplyJacobian

void MultiplyJacobian ( const Jacobian & jac, const JntArray & src, Twist & dest )

friend

Function to multiply a KDL::Jacobian with a KDL::JntArray to get a KDL::Twist, it should not be used to calculate the forward velocity kinematics, the solver classes are built for this purpose.

J*q = t

Parameters

jac	J
src	q
dest	t

Postcondition

dest==Twist::Zero() if 0==src.rows() (ie src is empty)

References KDL::Jacobian::data, data, and JntArray().

operator==

bool operator== ( const JntArray & src1, const JntArray & src2 )

friend

References KDL::Equal(), and JntArray().

SetToZero

void SetToZero ( JntArray & array )

friend

Function to set all the values of the array to 0.

Parameters

array

References data, and JntArray().

Subtract

void Subtract ( const JntArray & src1, const JntArray & src2, JntArray & dest )

friend

Function to subtract two joint arrays, all the arguments must have the same size: A - B = C.

This function is aliasing-safe, A or B can be the same array as C.

Parameters

src1	A
src2	B
dest	C

References data, and JntArray().

Member Data Documentation

data

Eigen::VectorXd KDL::JntArray::data

Referenced by Add, KDL::ChainIkSolverPos_LMA::CartToJnt(), KDL::ChainIkSolverVel_pinv::CartToJnt(), KDL::ChainIkSolverVel_pinv_nso::CartToJnt(), KDL::ChainIkSolverVel_wdls::CartToJnt(), KDL::TreeIkSolverVel_wdls::CartToJnt(), columns(), KDL::ChainHdSolver_Vereshchagin::constraint_calculation(), KDL::ChainIkSolverPos_LMA::display_jac(), Divide, Equal, KDL::ChainHdSolver_Vereshchagin::getTotalTorque(), JntArray(), JntArray(), KDL::ChainExternalWrenchEstimator::JntToExtWrench(), Multiply, KDL::Multiply(), MultiplyJacobian, operator()(), operator()(), operator=(), resize(), rows(), KDL::ChainExternalWrenchEstimator::setInitialMomentum(), SetToZero, and Subtract.

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

• src/jntarray.hpp
• src/jntarray.cpp