Visual Servoing Platform  version 3.6.1 under development (2024-05-20)
vpVelocityTwistMatrix Class Reference

#include <visp3/core/vpVelocityTwistMatrix.h>

+ Inheritance diagram for vpVelocityTwistMatrix:

Public Member Functions

 vpVelocityTwistMatrix ()
 
 vpVelocityTwistMatrix (const vpVelocityTwistMatrix &V)
 
 vpVelocityTwistMatrix (const vpHomogeneousMatrix &M, bool full=true)
 
 vpVelocityTwistMatrix (const vpTranslationVector &t, const vpRotationMatrix &R)
 
 vpVelocityTwistMatrix (const vpTranslationVector &t, const vpThetaUVector &thetau)
 
 vpVelocityTwistMatrix (double tx, double ty, double tz, double tux, double tuy, double tuz)
 
 vpVelocityTwistMatrix (const vpRotationMatrix &R)
 
 vpVelocityTwistMatrix (const vpThetaUVector &thetau)
 
vpVelocityTwistMatrix buildFrom (const vpTranslationVector &t, const vpRotationMatrix &R)
 
vpVelocityTwistMatrix buildFrom (const vpTranslationVector &t, const vpThetaUVector &thetau)
 
vpVelocityTwistMatrix buildFrom (const vpHomogeneousMatrix &M, bool full=true)
 
vpVelocityTwistMatrix buildFrom (const vpRotationMatrix &R)
 
vpVelocityTwistMatrix buildFrom (const vpThetaUVector &thetau)
 
void extract (vpRotationMatrix &R) const
 
void extract (vpTranslationVector &t) const
 
void eye ()
 
vpVelocityTwistMatrix inverse () const
 
void inverse (vpVelocityTwistMatrix &V) const
 
vpVelocityTwistMatrix operator* (const vpVelocityTwistMatrix &V) const
 
vpMatrix operator* (const vpMatrix &M) const
 
vpColVector operator* (const vpColVector &v) const
 
vpVelocityTwistMatrixoperator= (const vpVelocityTwistMatrix &V)
 
int print (std::ostream &s, unsigned int length, char const *intro=0) const
 
void resize (unsigned int nrows, unsigned int ncols, bool flagNullify=true)
 
Deprecated functions
vp_deprecated void init ()
 
vp_deprecated void setIdentity ()
 
Inherited functionalities from vpArray2D
unsigned int getCols () const
 
double getMaxValue () const
 
double getMinValue () const
 
unsigned int getRows () const
 
unsigned int size () const
 
void resize (unsigned int nrows, unsigned int ncols, bool flagNullify=true, bool recopy_=true)
 
void reshape (unsigned int nrows, unsigned int ncols)
 
void insert (const vpArray2D< double > &A, unsigned int r, unsigned int c)
 
bool operator== (const vpArray2D< double > &A) const
 
bool operator!= (const vpArray2D< double > &A) const
 
double * operator[] (unsigned int i)
 
double * operator[] (unsigned int i) const
 
vpArray2D< double > hadamard (const vpArray2D< double > &m) const
 
vpArray2D< double > t () const
 

Public Attributes

double * data
 

Protected Attributes

unsigned int rowNum
 
unsigned int colNum
 
double ** rowPtrs
 
unsigned int dsize
 

Friends

class vpMatrix
 

Related Functions

(Note that these are not member functions.)

enum  vpGEMMmethod
 
bool operator== (const vpArray2D< double > &A) const
 
bool operator== (const vpArray2D< float > &A) const
 
bool operator!= (const vpArray2D< double > &A) const
 
void vpGEMM (const vpArray2D< double > &A, const vpArray2D< double > &B, const double &alpha, const vpArray2D< double > &C, const double &beta, vpArray2D< double > &D, const unsigned int &ops=0)
 

Inherited I/O from vpArray2D with Static Public Member Functions

vpArray2D< double > insert (const vpArray2D< double > &A, const vpArray2D< double > &B, unsigned int r, unsigned int c)
 
static void insert (const vpArray2D< double > &A, const vpArray2D< double > &B, vpArray2D< double > &C, unsigned int r, unsigned int c)
 
static bool load (const std::string &filename, vpArray2D< double > &A, bool binary=false, char *header=nullptr)
 
static bool loadYAML (const std::string &filename, vpArray2D< double > &A, char *header=nullptr)
 
static bool save (const std::string &filename, const vpArray2D< double > &A, bool binary=false, const char *header="")
 
static bool saveYAML (const std::string &filename, const vpArray2D< double > &A, const char *header="")
 
static vpArray2D< double > conv2 (const vpArray2D< double > &M, const vpArray2D< double > &kernel, const std::string &mode)
 
static void conv2 (const vpArray2D< double > &M, const vpArray2D< double > &kernel, vpArray2D< double > &res, const std::string &mode)
 

Detailed Description

This class derived from vpArray2D<double> implements the 6 by 6 matrix which transforms velocities from one frame to another. This matrix is also called velocity twist transformation matrix.

The full velocity twist transformation matrix allows to compute the velocity at point a expressed in frame a knowing its velocity at point b expressed in frame b. This matrix is defined as:

\[ ^a{\bf V}_b = \left[\begin{array}{cc} ^a{\bf R}_b & [^a{\bf t}_b]_\times \; ^a{\bf R}_b\\ {\bf 0}_{3\times 3} & ^a{\bf R}_b \end{array} \right] \]

where $ ^a{\bf R}_b $ is a rotation matrix and $ ^a{\bf t}_b $ is a translation vector.

There are different ways to initialize such a full velocity twist matrix. The following example shows how to proceed setting the translation and rotation matrix transformations:

#include <visp3/core/vpVelocityTwistMatrix.h>
int main()
{
vpTranslationVector cte(0.1, 0.2, 0.3);
vpRotationMatrix cRe( {0, 0, -1,
0, -1, 0,
-1, 0, 0} );
vpVelocityTwistMatrix cVe(cte, cRe);
std::cout << "cVe:\n" << cVe << std::endl;
}
Implementation of a rotation matrix and operations on such kind of matrices.
Class that consider the case of a translation vector.

It produces the following printings:

cVe:
0 0 -1 -0.2 0.3 0
0 -1 0 0.1 0 -0.3
-1 0 0 0 -0.1 0.2
0 0 0 0 0 -1
0 0 0 0 -1 0
0 0 0 -1 0 0

When the point where the velocity is expressed doesn't change, the matrix becomes block diagonal. It allows than to compute the velocity at point b expressed in frame a knowing its velocity at point b expressed in frame b :

\[ ^a{\bf V}_b = \left[\begin{array}{cc} ^a{\bf R}_b & {\bf 0}_{3\times 3} \\ {\bf 0}_{3\times 3} & ^a{\bf R}_b \end{array} \right] \]

To initialize such a velocity twist matrix where translation is not taken into account you can proceed like in the following code:

#include <visp3/core/vpVelocityTwistMatrix.h>
int main()
{
vpRotationMatrix cRe( {0, 0, -1,
0, -1, 0,
-1, 0, 0} );
std::cout << "cVe:\n" << cVe << std::endl;
}

It produces the following printings:

cVe:
0 0 -1 0 0 0
0 -1 0 0 0 0
-1 0 0 0 0 0
0 0 0 0 0 -1
0 0 0 0 -1 0
0 0 0 -1 0 0

The code below shows how to convert a velocity skew expressed at the origin of the camera frame into the origin of the fix frame using the full velocity twist matrix.

#include <visp3/core/vpColVector.h>
#include <visp3/core/vpVelocityTwistMatrix.h>
int main()
{
vpVelocityTwistMatrix fVc; // Twist transformation matrix from fix to camera frame
vpHomogeneousMatrix fMc; // Fix to camera frame transformation
// ... fMc need here to be initialized
fVc.buildFrom(fMc);
vpColVector c_v(6); // Velocity in the camera frame: vx,vy,vz,wx,wy,wz
// ... c_v should here have an initial value
vpColVector f_v(6); // Velocity in the fix frame: vx,vy,vz,wx,wy,wz
// Compute the velocity in the fix frame
f_v = fVc * c_v;
}
Implementation of column vector and the associated operations.
Definition: vpColVector.h:163
Implementation of an homogeneous matrix and operations on such kind of matrices.
vpVelocityTwistMatrix buildFrom(const vpTranslationVector &t, const vpRotationMatrix &R)
Examples
manServo4PointsDisplay.cpp, manSimu4Dots.cpp, manSimu4Points.cpp, mbot-apriltag-2D-half-vs.cpp, mbot-apriltag-ibvs.cpp, mbot-apriltag-pbvs.cpp, servoAfma4Point2DArtVelocity.cpp, servoAfma6FourPoints2DArtVelocity.cpp, servoAfma6Point2DArtVelocity.cpp, servoBebop2.cpp, servoBiclopsPoint2DArtVelocity.cpp, servoFlirPtuIBVS.cpp, servoPioneerPanSegment3D.cpp, servoPioneerPoint2DDepth.cpp, servoPioneerPoint2DDepthWithoutVpServo.cpp, servoPololuPtuPoint2DJointVelocity.cpp, servoPtu46Point2DArtVelocity.cpp, servoSimu4Points.cpp, servoSimuCylinder.cpp, servoSimuFourPoints2DCamVelocity.cpp, servoSimuFourPoints2DCamVelocityDisplay.cpp, servoSimuFourPoints2DPolarCamVelocityDisplay.cpp, servoSimuPoint2DCamVelocity2.cpp, servoSimuPoint2DCamVelocity3.cpp, servoSimuSphere.cpp, servoViper650FourPoints2DArtVelocityLs_cur.cpp, servoViper850FourPoints2DArtVelocityLs_cur.cpp, servoViper850FourPoints2DArtVelocityLs_des.cpp, servoViper850Point2DArtVelocity-jointAvoidance-basic.cpp, servoViper850Point2DArtVelocity-jointAvoidance-gpa.cpp, servoViper850Point2DArtVelocity-jointAvoidance-large.cpp, servoViper850Point2DArtVelocity.cpp, simulateFourPoints2DCartesianCamVelocity.cpp, simulateFourPoints2DPolarCamVelocity.cpp, testMatrix.cpp, testRobotViper650-frames.cpp, testRobotViper850-frames.cpp, testTwistMatrix.cpp, testVirtuoseAfma6.cpp, testVirtuoseHapticBox.cpp, tutorial-flir-ptu-ibvs.cpp, tutorial-simu-pioneer-continuous-gain-adaptive.cpp, tutorial-simu-pioneer-continuous-gain-constant.cpp, tutorial-simu-pioneer-pan.cpp, and tutorial-simu-pioneer.cpp.

Definition at line 160 of file vpVelocityTwistMatrix.h.

Constructor & Destructor Documentation

◆ vpVelocityTwistMatrix() [1/8]

vpVelocityTwistMatrix::vpVelocityTwistMatrix ( )

Initialize a velocity twist transformation matrix as identity.

Definition at line 86 of file vpVelocityTwistMatrix.cpp.

References eye().

◆ vpVelocityTwistMatrix() [2/8]

vpVelocityTwistMatrix::vpVelocityTwistMatrix ( const vpVelocityTwistMatrix V)

Initialize a velocity twist transformation matrix from another velocity twist matrix.

Parameters
V: Velocity twist matrix used as initializer.

Definition at line 94 of file vpVelocityTwistMatrix.cpp.

◆ vpVelocityTwistMatrix() [3/8]

vpVelocityTwistMatrix::vpVelocityTwistMatrix ( const vpHomogeneousMatrix M,
bool  full = true 
)
explicit

Initialize a velocity twist transformation matrix from an homogeneous matrix $M$ with

\[ {\bf M} = \left[\begin{array}{cc} {\bf R} & {\bf t} \\ {\bf 0}_{1\times 3} & 1 \end{array} \right] \]

Parameters
M: Homogeneous matrix $\bf M$ used to initialize the velocity twist transformation matrix.
full: Boolean used to indicate which matrix should be filled.
  • When set to true, use the complete velocity skew transformation :

    \[ {\bf V} = \left[\begin{array}{cc} {\bf R} & [{\bf t}]_\times \; {\bf R} \\ {\bf 0}_{3\times 3} & {\bf R} \end{array} \right] \]

  • When set to false, use the block diagonal velocity skew transformation:

    \[ {\bf V} = \left[\begin{array}{cc} {\bf R} & {\bf 0}_{3\times 3} \\ {\bf 0}_{3\times 3} & {\bf R} \end{array} \right] \]

Definition at line 114 of file vpVelocityTwistMatrix.cpp.

References buildFrom(), and vpHomogeneousMatrix::getRotationMatrix().

◆ vpVelocityTwistMatrix() [4/8]

vpVelocityTwistMatrix::vpVelocityTwistMatrix ( const vpTranslationVector t,
const vpRotationMatrix R 
)

Initialize a velocity twist transformation matrix from a translation vector t and a rotation matrix R.

\[ {\bf V} = \left[\begin{array}{cc} {\bf R} & [{\bf t}]_\times \; {\bf R} \\ {\bf 0}_{3\times 3} & {\bf R} \end{array} \right] \]

Parameters
t: Translation vector.
R: Rotation matrix.

Definition at line 174 of file vpVelocityTwistMatrix.cpp.

References buildFrom(), and vpArray2D< double >::t().

◆ vpVelocityTwistMatrix() [5/8]

vpVelocityTwistMatrix::vpVelocityTwistMatrix ( const vpTranslationVector t,
const vpThetaUVector thetau 
)

Initialize a velocity twist transformation matrix from a translation vector t and a rotation vector with $\theta u $ parametrization.

\[ {\bf V} = \left[\begin{array}{cc} {\bf R} & [{\bf t}]_\times \; {\bf R} \\ {\bf 0}_{3\times 3} & {\bf R} \end{array} \right] \]

Parameters
t: Translation vector.
thetau: $\theta u$ rotation vector used to initialize rotation vector $R$ .

Definition at line 138 of file vpVelocityTwistMatrix.cpp.

References buildFrom(), and vpArray2D< double >::t().

◆ vpVelocityTwistMatrix() [6/8]

vpVelocityTwistMatrix::vpVelocityTwistMatrix ( double  tx,
double  ty,
double  tz,
double  tux,
double  tuy,
double  tuz 
)

Initialize a velocity twist transformation matrix from a translation vector ${\bf t}=(t_x, t_y, t_z)^T$ and a rotation vector with $\theta {\bf u}=(\theta u_x, \theta u_y, \theta u_z)^T $ parametrization.

\[ {\bf V} = \left[\begin{array}{cc} {\bf R} & [{\bf t}]_\times \; {\bf R} \\ {\bf 0}_{3\times 3} & {\bf R} \end{array} \right] \]

Parameters
tx,ty,tz: Translation vector in meters.
tux,tuy,tuz: $\theta {\bf u}$ rotation vector expressed in radians used to initialize $R$.

Definition at line 208 of file vpVelocityTwistMatrix.cpp.

References buildFrom(), and vpArray2D< double >::t().

◆ vpVelocityTwistMatrix() [7/8]

vpVelocityTwistMatrix::vpVelocityTwistMatrix ( const vpRotationMatrix R)
explicit

Initialize a velocity twist transformation matrix from a rotation matrix R.

\[ {\bf V} = \left[\begin{array}{cc} {\bf R} & {\bf 0}_{3\times 3} \\ {\bf 0}_{3\times 3} & {\bf R} \end{array} \right] \]

Parameters
R: Rotation matrix.

Definition at line 191 of file vpVelocityTwistMatrix.cpp.

References buildFrom().

◆ vpVelocityTwistMatrix() [8/8]

vpVelocityTwistMatrix::vpVelocityTwistMatrix ( const vpThetaUVector thetau)
explicit

Initialize a velocity twist transformation matrix from a rotation vector with $\theta u $ parametrization.

\[ {\bf V} = \left[\begin{array}{cc} {\bf R} & {\bf 0}_{3\times 3}\\ {\bf 0}_{3\times 3} & {\bf R} \end{array} \right] \]

Parameters
thetau: $\theta u$ rotation vector used to initialize rotation vector $R$ .

Definition at line 156 of file vpVelocityTwistMatrix.cpp.

References buildFrom().

Member Function Documentation

◆ buildFrom() [1/5]

vpVelocityTwistMatrix vpVelocityTwistMatrix::buildFrom ( const vpHomogeneousMatrix M,
bool  full = true 
)

Initialize a velocity twist transformation matrix from an homogeneous matrix $M$ with

\[ {\bf M} = \left[\begin{array}{cc} {\bf R} & {\bf t} \\ {\bf 0}_{1\times 3} & 1 \end{array} \right] \]

Parameters
M: Homogeneous matrix $M$ used to initialize the velocity twist transformation matrix.
full: Boolean used to indicate which matrix should be filled.
  • When set to true, use the complete velocity skew transformation :

    \[ {\bf V} = \left[\begin{array}{cc} {\bf R} & [{\bf t}]_\times \; {\bf R} \\ {\bf 0}_{3\times 3} & {\bf R} \end{array} \right] \]

  • When set to false, use the block diagonal velocity skew transformation:

    \[ {\bf V} = \left[\begin{array}{cc} {\bf R} & {\bf 0}_{3\times 3} \\ {\bf 0}_{3\times 3} & {\bf R} \end{array} \right] \]

Definition at line 440 of file vpVelocityTwistMatrix.cpp.

References buildFrom(), vpHomogeneousMatrix::getRotationMatrix(), and vpHomogeneousMatrix::getTranslationVector().

◆ buildFrom() [2/5]

vpVelocityTwistMatrix vpVelocityTwistMatrix::buildFrom ( const vpRotationMatrix R)

Build a velocity twist transformation block diagonal matrix from a rotation matrix R.

\[ {\bf V} = \left[\begin{array}{cc} {\bf R} & {\bf 0}_{3\times 3} \\ {\bf 0}_{3\times 3} & {\bf R} \end{array} \right] \]

Parameters
R: Rotation matrix.

Definition at line 342 of file vpVelocityTwistMatrix.cpp.

◆ buildFrom() [3/5]

vpVelocityTwistMatrix vpVelocityTwistMatrix::buildFrom ( const vpThetaUVector thetau)

Initialize a velocity twist transformation matrix from a rotation vector with $\theta u $ parametrization.

\[ {\bf V} = \left[\begin{array}{cc} {\bf R} & {\bf 0}_{3\times 3} \\ {\bf 0}_{3\times 3} & {\bf R} \end{array} \right] \]

Parameters
thetau: $\theta {\bf u}$ rotation vector used to create rotation matrix ${\bf R}$.

Definition at line 416 of file vpVelocityTwistMatrix.cpp.

References buildFrom().

◆ buildFrom() [4/5]

◆ buildFrom() [5/5]

vpVelocityTwistMatrix vpVelocityTwistMatrix::buildFrom ( const vpTranslationVector t,
const vpThetaUVector thetau 
)

Initialize a velocity twist transformation matrix from a translation vector t and a rotation vector with $\theta u $ parametrization.

\[ {\bf V} = \left[\begin{array}{cc} {\bf R} & [{\bf t}]_\times \; {\bf R} \\ {\bf 0}_{3\times 3} & {\bf R} \end{array} \right] \]

Parameters
t: Translation vector.
thetau: $\theta {\bf u}$ rotation vector used to create rotation matrix ${\bf R}$.

Definition at line 398 of file vpVelocityTwistMatrix.cpp.

References buildFrom(), and vpArray2D< double >::t().

◆ conv2() [1/2]

vpArray2D< double > vpArray2D< double >::conv2 ( const vpArray2D< Type > &  M,
const vpArray2D< Type > &  kernel,
const std::string &  mode 
)
staticinherited

Perform a 2D convolution similar to Matlab conv2 function: $ M \star kernel $.

Parameters
M: First matrix.
kernel: Second matrix.
mode: Convolution mode: "full" (default), "same", "valid".
Convolution mode: full, same, valid (image credit: Theano doc).
Note
This is a very basic implementation that does not use FFT.
Examples
testMatrixConvolution.cpp.

Definition at line 1038 of file vpArray2D.h.

◆ conv2() [2/2]

void vpArray2D< double >::conv2 ( const vpArray2D< Type > &  M,
const vpArray2D< Type > &  kernel,
vpArray2D< Type > &  res,
const std::string &  mode 
)
staticinherited

Perform a 2D convolution similar to Matlab conv2 function: $ M \star kernel $.

Parameters
M: First array.
kernel: Second array.
res: Result.
mode: Convolution mode: "full" (default), "same", "valid".
Convolution mode: full, same, valid (image credit: Theano doc).
Note
This is a very basic implementation that does not use FFT.

Definition at line 1052 of file vpArray2D.h.

◆ extract() [1/2]

void vpVelocityTwistMatrix::extract ( vpRotationMatrix R) const

Extract the rotation matrix from the velocity twist matrix.

Definition at line 472 of file vpVelocityTwistMatrix.cpp.

Referenced by extract(), and inverse().

◆ extract() [2/2]

void vpVelocityTwistMatrix::extract ( vpTranslationVector t) const

Extract the translation vector from the velocity twist matrix.

Definition at line 482 of file vpVelocityTwistMatrix.cpp.

References extract(), and vpRotationMatrix::t().

◆ eye()

void vpVelocityTwistMatrix::eye ( )

Initialize a 6x6 velocity twist matrix as identity.

Definition at line 69 of file vpVelocityTwistMatrix.cpp.

Referenced by setIdentity(), and vpVelocityTwistMatrix().

◆ getCols()

◆ getMaxValue()

double vpArray2D< double >::getMaxValue
inherited

Return the array max value.

Examples
servoMomentImage.cpp.

Definition at line 331 of file vpArray2D.h.

◆ getMinValue()

double vpArray2D< double >::getMinValue
inherited

Return the array min value.

Examples
servoMomentImage.cpp.

Definition at line 333 of file vpArray2D.h.

◆ getRows()

◆ hadamard()

vpArray2D< double > vpArray2D< double >::hadamard ( const vpArray2D< Type > &  m) const
inherited

Compute the Hadamard product (element wise matrix multiplication).

Parameters
m: Second matrix;
Returns
m1.hadamard(m2) The Hadamard product : $ m1 \circ m2 = (m1 \circ m2)_{i,j} = (m1)_{i,j} (m2)_{i,j} $
Examples
testArray2D.cpp.

Definition at line 630 of file vpArray2D.h.

◆ init()

vp_deprecated void vpVelocityTwistMatrix::init ( )
inline
Deprecated:
Provided only for compat with previous releases. This function does nothing.

Definition at line 226 of file vpVelocityTwistMatrix.h.

◆ insert() [1/2]

vpArray2D< double > vpArray2D< double >::insert ( const vpArray2D< Type > &  A,
const vpArray2D< Type > &  B,
unsigned int  r,
unsigned int  c 
)
inherited

Insert array B in array A at the given position.

Parameters
A: Main array.
B: Array to insert.
r: Index of the row where to add the array.
c: Index of the column where to add the array.
Returns
Array with B insert in A.
Warning
Throw exception if the sizes of the arrays do not allow the insertion.

Definition at line 1066 of file vpArray2D.h.

◆ insert() [2/2]

void vpArray2D< double >::insert ( const vpArray2D< Type > &  A,
unsigned int  r,
unsigned int  c 
)
inlineinherited

Insert array A at the given position in the current array.

Warning
Throw vpException::dimensionError if the dimensions of the matrices do not allow the operation.
Parameters
A: The array to insert.
r: The index of the row to begin to insert data.
c: The index of the column to begin to insert data.

Definition at line 486 of file vpArray2D.h.

◆ inverse() [1/2]

vpVelocityTwistMatrix vpVelocityTwistMatrix::inverse ( ) const

Invert the velocity twist matrix.

Definition at line 453 of file vpVelocityTwistMatrix.cpp.

References buildFrom(), extract(), and vpRotationMatrix::t().

Referenced by inverse().

◆ inverse() [2/2]

void vpVelocityTwistMatrix::inverse ( vpVelocityTwistMatrix V) const

Invert the velocity twist matrix.

Definition at line 469 of file vpVelocityTwistMatrix.cpp.

References inverse().

◆ load()

static bool vpArray2D< double >::load ( const std::string &  filename,
vpArray2D< Type > &  A,
bool  binary = false,
char *  header = nullptr 
)
inlinestaticinherited

Load a matrix from a file.

Parameters
filename: Absolute file name.
A: Array to be loaded
binary: If true the matrix is loaded from a binary file, else from a text file.
header: Header of the file is loaded in this parameter.
Returns
Returns true if success.
See also
save()

Definition at line 658 of file vpArray2D.h.

◆ loadYAML()

static bool vpArray2D< double >::loadYAML ( const std::string &  filename,
vpArray2D< Type > &  A,
char *  header = nullptr 
)
inlinestaticinherited

Load an array from a YAML-formatted file.

Parameters
filename: absolute file name.
A: array to be loaded from the file.
header: header of the file is loaded in this parameter.
Returns
Returns true on success.
See also
saveYAML()
Examples
servoFlirPtuIBVS.cpp, servoFrankaIBVS.cpp, servoFrankaPBVS.cpp, servoUniversalRobotsIBVS.cpp, servoUniversalRobotsPBVS.cpp, tutorial-flir-ptu-ibvs.cpp, tutorial-hsv-segmentation-pcl-viewer.cpp, tutorial-hsv-segmentation-pcl.cpp, and tutorial-hsv-segmentation.cpp.

Definition at line 772 of file vpArray2D.h.

◆ operator!=()

bool operator!= ( const vpArray2D< Type > &  A) const
inherited

Not equal to comparison operator of a 2D array.

Definition at line 512 of file vpArray2D.h.

◆ operator*() [1/3]

vpColVector vpVelocityTwistMatrix::operator* ( const vpColVector v) const

Operator that allows to multiply a twist transformation matrix by a 6-dimension column vector.

Parameters
v: Velocity skew vector.
Exceptions
vpException::dimensionErrorIf v is not a 6 dimension column vector.

Definition at line 309 of file vpVelocityTwistMatrix.cpp.

References vpException::dimensionError, vpArray2D< Type >::getRows(), and vpArray2D< double >::rowPtrs.

◆ operator*() [2/3]

vpMatrix vpVelocityTwistMatrix::operator* ( const vpMatrix M) const

Operator that allows to multiply a velocity twist transformation matrix by a matrix.

As shown in the example below, this operator can be used to compute the corresponding camera velocity skew from the joint velocities knowing the robot jacobian.

#include <visp3/core/vpColVector.h>
#include <visp3/core/vpConfig.h>
#include <visp3/core/vpVelocityTwistMatrix.h>
#include <visp3/robot/vpSimulatorCamera.h>
int main()
{
vpColVector q_vel(6); // Joint velocity on the 6 joints
// ... q_vel need here to be initialized
vpColVector c_v(6); // Velocity in the camera frame: vx,vy,vz,wx,wy,wz
vpVelocityTwistMatrix cVe; // Velocity skew transformation from camera frame to end-effector
robot.get_cVe(cVe);
vpMatrix eJe; // Robot jacobian
robot.get_eJe(eJe);
// Compute the velocity in the camera frame
c_v = cVe * eJe * q_vel;
return 0;
}
Implementation of a matrix and operations on matrices.
Definition: vpMatrix.h:146
void get_eJe(vpMatrix &eJe) vp_override
Class that defines the simplest robot: a free flying camera.
vpVelocityTwistMatrix get_cVe() const
Definition: vpUnicycle.h:70
Exceptions
vpException::dimensionErrorIf M is not a 6 rows dimension matrix.

Definition at line 277 of file vpVelocityTwistMatrix.cpp.

References vpException::dimensionError, vpArray2D< Type >::getCols(), vpArray2D< Type >::getRows(), and vpArray2D< double >::rowPtrs.

◆ operator*() [3/3]

vpVelocityTwistMatrix vpVelocityTwistMatrix::operator* ( const vpVelocityTwistMatrix V) const

Operator that allows to multiply a velocity twist transformation matrix by an other velocity twist transformation matrix.

Definition at line 222 of file vpVelocityTwistMatrix.cpp.

References vpArray2D< Type >::rowPtrs, and vpArray2D< double >::rowPtrs.

◆ operator=()

vpVelocityTwistMatrix & vpVelocityTwistMatrix::operator= ( const vpVelocityTwistMatrix V)

Copy operator that allow to set a velocity twist matrix from an other one.

Parameters
V: Velocity twist matrix to copy.

Definition at line 55 of file vpVelocityTwistMatrix.cpp.

References vpArray2D< Type >::rowPtrs, and vpArray2D< double >::rowPtrs.

◆ operator==()

bool vpArray2D< double >::operator== ( const vpArray2D< Type > &  A) const
inherited

Equal to comparison operator of a 2D array.

Definition at line 508 of file vpArray2D.h.

◆ operator[]() [1/2]

double * vpArray2D< double >::operator[] ( unsigned int  i)
inlineinherited

Set element $A_{ij} = x$ using A[i][j] = x.

Definition at line 594 of file vpArray2D.h.

◆ operator[]() [2/2]

double * vpArray2D< double >::operator[] ( unsigned int  i) const
inlineinherited

Get element $x = A_{ij}$ using x = A[i][j].

Definition at line 596 of file vpArray2D.h.

◆ print()

int vpVelocityTwistMatrix::print ( std::ostream &  s,
unsigned int  length,
char const *  intro = 0 
) const

Pretty print a velocity twist matrix. The data are tabulated. The common widths before and after the decimal point are set with respect to the parameter maxlen.

Parameters
sStream used for the printing.
lengthThe suggested width of each matrix element. The actual width grows in order to accommodate the whole integral part, and shrinks if the whole extent is not needed for all the numbers.
introThe introduction which is printed before the matrix. Can be set to zero (or omitted), in which case the introduction is not printed.
Returns
Returns the common total width for all matrix elements
See also
std::ostream &operator<<(std::ostream &s, const vpArray2D<Type> &A)
Examples
testTwistMatrix.cpp.

Definition at line 518 of file vpVelocityTwistMatrix.cpp.

References vpArray2D< double >::getCols(), vpArray2D< double >::getRows(), vpMath::maximum(), and vpArray2D< double >::size().

◆ reshape()

void vpArray2D< double >::reshape ( unsigned int  nrows,
unsigned int  ncols 
)
inlineinherited
Examples
testMatrixInitialization.cpp.

Definition at line 445 of file vpArray2D.h.

◆ resize() [1/2]

void vpVelocityTwistMatrix::resize ( unsigned int  nrows,
unsigned int  ncols,
bool  flagNullify = true 
)
inline

This function is not applicable to a velocity twist matrix that is always a 6-by-6 matrix.

Exceptions
vpException::fatalErrorWhen this function is called.

Definition at line 209 of file vpVelocityTwistMatrix.h.

References vpException::fatalError.

◆ resize() [2/2]

void vpArray2D< double >::resize ( unsigned int  nrows,
unsigned int  ncols,
bool  flagNullify = true,
bool  recopy_ = true 
)
inlineinherited

Set the size of the array and initialize all the values to zero.

Parameters
nrows: number of rows.
ncols: number of column.
flagNullify: if true, then the array is re-initialized to 0 after resize. If false, the initial values from the common part of the array (common part between old and new version of the array) are kept. Default value is true.
recopy_: if true, will perform an explicit recopy of the old data.
Examples
testArray2D.cpp, testMatrix.cpp, testMatrixDeterminant.cpp, testMatrixInverse.cpp, testMatrixPseudoInverse.cpp, and testSvd.cpp.

Definition at line 354 of file vpArray2D.h.

◆ save()

static bool vpArray2D< double >::save ( const std::string &  filename,
const vpArray2D< Type > &  A,
bool  binary = false,
const char *  header = "" 
)
inlinestaticinherited

Save a matrix to a file.

Parameters
filename: Absolute file name.
A: Array to be saved.
binary: If true the matrix is saved in a binary file, else a text file.
header: Optional line that will be saved at the beginning of the file.
Returns
Returns true if success.

Warning : If you save the matrix as in a text file the precision is less than if you save it in a binary file.

See also
load()

Definition at line 860 of file vpArray2D.h.

◆ saveYAML()

static bool vpArray2D< double >::saveYAML ( const std::string &  filename,
const vpArray2D< Type > &  A,
const char *  header = "" 
)
inlinestaticinherited

Save an array in a YAML-formatted file.

Parameters
filename: absolute file name.
A: array to be saved in the file.
header: optional lines that will be saved at the beginning of the file. Should be YAML-formatted and will adapt to the indentation if any.
Returns
Returns true if success.

Here is an example of outputs.

vpArray2D::saveYAML("matrix.yml", M, "example: a YAML-formatted header");
vpArray2D::saveYAML("matrixIndent.yml", M, "example:\n - a YAML-formatted \
header\n - with inner indentation");
static bool saveYAML(const std::string &filename, const vpArray2D< Type > &A, const char *header="")
Definition: vpArray2D.h:957

Content of matrix.yml:

example: a YAML-formatted header
rows: 3
cols: 4
- [0, 0, 0, 0]
- [0, 0, 0, 0]
- [0, 0, 0, 0]
double * data
Address of the first element of the data array.
Definition: vpArray2D.h:139

Content of matrixIndent.yml:

example:
- a YAML-formatted header
- with inner indentation
rows: 3
cols: 4
- [0, 0, 0, 0]
- [0, 0, 0, 0]
- [0, 0, 0, 0]
See also
loadYAML()

Definition at line 957 of file vpArray2D.h.

◆ setIdentity()

void vpVelocityTwistMatrix::setIdentity ( )
Deprecated:
You should rather use eye().
Deprecated:
You should rather use eye().

Set the velocity twist transformation matrix to identity.

Definition at line 617 of file vpVelocityTwistMatrix.cpp.

References eye().

◆ size()

◆ t()

vpArray2D< double > vpArray2D< double >::t
inherited

Compute the transpose of the array.

Returns
vpArray2D<Type> C = A^T

Definition at line 637 of file vpArray2D.h.

Friends And Related Function Documentation

◆ insert()

void vpArray2D< double >::insert ( const vpArray2D< Type > &  A,
const vpArray2D< Type > &  B,
vpArray2D< Type > &  C,
unsigned int  r,
unsigned int  c 
)
related

Insert array B in array A at the given position.

Parameters
A: Main array.
B: Array to insert.
C: Result array.
r: Index of the row where to insert array B.
c: Index of the column where to insert array B.
Warning
Throw exception if the sizes of the arrays do not allow the insertion.

Definition at line 1081 of file vpArray2D.h.

◆ operator!=()

bool operator!= ( const vpArray2D< Type > &  A) const
related

Definition at line 1325 of file vpArray2D.h.

◆ operator==() [1/2]

bool operator== ( const vpArray2D< double > &  A) const
related

Definition at line 1287 of file vpArray2D.h.

◆ operator==() [2/2]

bool operator== ( const vpArray2D< float > &  A) const
related

Definition at line 1306 of file vpArray2D.h.

◆ vpGEMM()

void vpGEMM ( const vpArray2D< double > &  A,
const vpArray2D< double > &  B,
const double &  alpha,
const vpArray2D< double > &  C,
const double &  beta,
vpArray2D< double > &  D,
const unsigned int &  ops = 0 
)
related

This function performs generalized matrix multiplication: D = alpha*op(A)*op(B) + beta*op(C), where op(X) is X or X^T. Operation on A, B and C matrices is described by enumeration vpGEMMmethod().

For example, to compute D = alpha*A^T*B^T+beta*C we need to call :

vpGEMM(A, B, alpha, C, beta, D, VP_GEMM_A_T + VP_GEMM_B_T);
void vpGEMM(const vpArray2D< double > &A, const vpArray2D< double > &B, const double &alpha, const vpArray2D< double > &C, const double &beta, vpArray2D< double > &D, const unsigned int &ops=0)
Definition: vpGEMM.h:413

If C is not used, vpGEMM must be called using an empty array null. Thus to compute D = alpha*A^T*B, we have to call:

vpGEMM(A, B, alpha, null, 0, D, VP_GEMM_B_T);
Exceptions
vpException::incorrectMatrixSizeErrorif the sizes of the matrices do not allow the operations.
Parameters
A: An array that could be a vpMatrix.
B: An array that could be a vpMatrix.
alpha: A scalar.
C: An array that could be a vpMatrix.
beta: A scalar.
D: The resulting array that could be a vpMatrix.
ops: A scalar describing operation applied on the matrices. Possible values are the one defined in vpGEMMmethod(): VP_GEMM_A_T, VP_GEMM_B_T, VP_GEMM_C_T.

Definition at line 413 of file vpGEMM.h.

◆ vpGEMMmethod

enum vpGEMMmethod
related

Enumeration of the operations applied on matrices in vpGEMM() function.

Operations are :

  • VP_GEMM_A_T to use the transpose matrix of A instead of the matrix A
  • VP_GEMM_B_T to use the transpose matrix of B instead of the matrix B
  • VP_GEMM_C_T to use the transpose matrix of C instead of the matrix C

Definition at line 52 of file vpGEMM.h.

◆ vpMatrix

friend class vpMatrix
friend

Definition at line 162 of file vpVelocityTwistMatrix.h.

Member Data Documentation

◆ colNum

unsigned int vpArray2D< double >::colNum
protectedinherited

Number of columns in the array.

Definition at line 131 of file vpArray2D.h.

◆ data

double * vpArray2D< double >::data
inherited

◆ dsize

unsigned int vpArray2D< double >::dsize
protectedinherited

Current array size (rowNum * colNum)

Definition at line 135 of file vpArray2D.h.

◆ rowNum

unsigned int vpArray2D< double >::rowNum
protectedinherited

Number of rows in the array.

Definition at line 129 of file vpArray2D.h.

◆ rowPtrs

double ** vpArray2D< double >::rowPtrs
protectedinherited

Address of the first element of each rows.

Definition at line 133 of file vpArray2D.h.