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

#include <jntarray.hpp>

Public Member Functions
unsigned int	columns () const

	JntArray ()

	JntArray (unsigned int size)

	JntArray (const JntArray &arg)

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

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

JntArray &	operator= (const JntArray &arg)

void	resize (unsigned int newSize)

unsigned int	rows () const

	~JntArray ()

Public Attributes
Eigen::VectorXd	data

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

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

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

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

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

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

void	SetToZero (JntArray &array)

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

Detailed Description

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
   }
};

Definition at line 69 of file jntarray.hpp.

Constructor & Destructor Documentation

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.

Definition at line 28 of file jntarray.cpp.

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

Definition at line 32 of file jntarray.cpp.

KDL::JntArray::JntArray ( const JntArray & arg )

Copy constructor

Note: Will correctly copy an empty object

Definition at line 39 of file jntarray.cpp.

KDL::JntArray::~JntArray ( )

Definition at line 51 of file jntarray.cpp.

Member Function Documentation

unsigned int KDL::JntArray::columns ( ) const

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

Definition at line 77 of file jntarray.cpp.

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)

Definition at line 60 of file jntarray.cpp.

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)

Definition at line 66 of file jntarray.cpp.

JntArray & KDL::JntArray::operator= ( const JntArray & arg )

Definition at line 44 of file jntarray.cpp.

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

Definition at line 55 of file jntarray.cpp.

unsigned int KDL::JntArray::rows ( ) const

Returns the number of rows (size) of the array

Definition at line 72 of file jntarray.cpp.

Friends And Related Function Documentation

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

Definition at line 82 of file jntarray.cpp.

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

Definition at line 97 of file jntarray.cpp.

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

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())

Definition at line 113 of file jntarray.cpp.

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

Definition at line 92 of file jntarray.cpp.

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)

Definition at line 102 of file jntarray.cpp.

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

friend

Definition at line 120 of file jntarray.cpp.

void SetToZero ( JntArray & array )

friend

Function to set all the values of the array to 0

Parameters

array

Definition at line 108 of file jntarray.cpp.

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

Definition at line 87 of file jntarray.cpp.

Member Data Documentation

Eigen::VectorXd KDL::JntArray::data

Definition at line 72 of file jntarray.hpp.

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

Public Member Functions

Public Attributes

Friends

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Friends And Related Function Documentation

Member Data Documentation