DGtal::AngleComputer Struct Reference

#include <AngleComputer.h>

Static Public Member Functions
static float	cast (float i)
static bool	less (float i, float j)
static float	posDiff (float j, float i)
static float	deviation (float j, float i)
static float	min (float i, float j)
static float	max (float i, float j)
static double	cast (double i)
static bool	less (double i, double j)
static double	posDiff (double j, double i)
static double	deviation (double j, double i)
static double	min (double i, double j)
static double	max (double i, double j)

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Detailed Description

A simple class to perform angle computations. All angles are in [0:2pi[

Definition at line 69 of file AngleComputer.h.

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Member Function Documentation

float DGtal::AngleComputer::cast ( float  i )

inlinestatic

Parameters:

i	any angle.

Returns:

the corresponding angle in [0:2pi[

Definition at line 54 of file AngleComputer.ih.

References M_PI.

Referenced by DGtal::AngleLinearMinimizer::oneStep(), DGtal::AngleLinearMinimizerByRelaxation::oneStep(), DGtal::AngleLinearMinimizerByGradientDescent::oneStep(), and DGtal::AngleLinearMinimizerByAdaptiveStepGradientDescent::oneStep().

{
  while ( i < 0.0f ) i += (float) (M_PI*2.0);
  while ( i > (double)(M_PI*2.0) ) i -= (float)(M_PI*2.0);
  return i;
}

double DGtal::AngleComputer::cast ( double  i )

inlinestatic

Parameters:

i	any angle.

Returns:

the corresponding angle in [0:2pi[

Definition at line 147 of file AngleComputer.ih.

References M_PI.

{
  while ( i < 0.0 ) i += (float)(M_PI*2.0);
  while ( i > (float)(M_PI*2.0) ) i -= (float)(M_PI*2.0);
  return i;
}

float DGtal::AngleComputer::deviation ( float  j, float  i  )

inlinestatic

Performs j - i, assuming th result is in [-pi:pi[

Parameters:

j	any angle in [0:2pi[
i	any angle in [0:2pi[

Returns:

the value j - i, always positive.

Definition at line 105 of file AngleComputer.ih.

Referenced by DGtal::AngleLinearMinimizer::getEnergy(), DGtal::AngleLinearMinimizer::getFormerEnergy(), DGtal::AngleLinearMinimizer::getFormerGradient(), DGtal::AngleLinearMinimizer::getGradient(), DGtal::AngleLinearMinimizer::oneStep(), DGtal::AngleLinearMinimizerByRelaxation::oneStep(), and DGtal::AngleLinearMinimizer::optimize().

{
  return less( i, j ) ? posDiff( j, i ) : -posDiff( i, j );
}

double DGtal::AngleComputer::deviation ( double  j, double  i  )

inlinestatic

Performs j - i, assuming th result is in [-pi:pi[

Parameters:

j	any angle in [0:2pi[
i	any angle in [0:2pi[

Returns:

the value j - i, always positive.

Definition at line 198 of file AngleComputer.ih.

{
  return less( i, j ) ? posDiff( j, i ) : -posDiff( i, j );
}

bool DGtal::AngleComputer::less ( float  i, float  j  )

inlinestatic

Less comparator modulo. Be careful, modulo comparisons have no sense when the absolute difference of the values are around pi.

Parameters:

i	any angle in [0:2pi[
j	any angle in [0:2pi[

Returns:

'true' if [i] strictly precedes [j] in a window 'pi'.

Definition at line 72 of file AngleComputer.ih.

References M_PI.

Referenced by DGtal::AngleLinearMinimizer::oneStep(), DGtal::AngleLinearMinimizerByRelaxation::oneStep(), DGtal::AngleLinearMinimizerByGradientDescent::oneStep(), and DGtal::AngleLinearMinimizerByAdaptiveStepGradientDescent::oneStep().

{
  float d = j - i;
  if ( d > 0.0f )
    return d < M_PI;
  else
    return (-d) >= M_PI;
}

bool DGtal::AngleComputer::less ( double  i, double  j  )

inlinestatic

Less comparator modulo. Be careful, modulo comparisons have no sense when the absolute difference of the values are around pi.

Parameters:

i	any angle in [0:2pi[
j	any angle in [0:2pi[

Returns:

'true' if [i] strictly precedes [j] in a window 'pi'.

Definition at line 165 of file AngleComputer.ih.

References M_PI.

{
  double d = j - i;
  if ( d > 0.0 )
    return d < M_PI;
  else
    return (-d) >= M_PI;
}

float DGtal::AngleComputer::max ( float  i, float  j  )

inlinestatic

Equivalent to 'less( i, j ) ? j : i'.

Parameters:

i	any angle in [0:2pi[
j	any angle in [0:2pi[

Returns:

the greatest angle of [i] and [j] in a window 'pi'.

Definition at line 134 of file AngleComputer.ih.

{
  return less( i, j ) ? j : i;
}

double DGtal::AngleComputer::max ( double  i, double  j  )

inlinestatic

Equivalent to 'less( i, j ) ? j : i'.

Parameters:

i	any angle in [0:2pi[
j	any angle in [0:2pi[

Returns:

the greatest angle of [i] and [j] in a window 'pi'.

Definition at line 227 of file AngleComputer.ih.

{
  return less( i, j ) ? j : i;
}

float DGtal::AngleComputer::min ( float  i, float  j  )

inlinestatic

Equivalent to 'less( i, j ) ? i : j'.

Parameters:

i	any angle in [0:2pi[
j	any angle in [0:2pi[

Returns:

the smallest angle of [i] and [j] in a window 'pi'.

Definition at line 120 of file AngleComputer.ih.

{
  return less( i, j ) ? i : j;
}

double DGtal::AngleComputer::min ( double  i, double  j  )

inlinestatic

Equivalent to 'less( i, j ) ? i : j'.

Parameters:

i	any angle in [0:2pi[
j	any angle in [0:2pi[

Returns:

the smallest angle of [i] and [j] in a window 'pi'.

Definition at line 213 of file AngleComputer.ih.

{
  return less( i, j ) ? i : j;
}

float DGtal::AngleComputer::posDiff ( float  j, float  i  )

inlinestatic

Performs j - i modulo 2pi, assuming less(i,j) is true.

Parameters:

j	any angle in [0:2pi[
i	any angle in [0:2pi[

Returns:

the value j - i, always positive.

Definition at line 91 of file AngleComputer.ih.

References M_PI.

{
  return ( i <= j ) ? j - i : j + (float)(M_PI*2.0) - i;
}

double DGtal::AngleComputer::posDiff ( double  j, double  i  )

inlinestatic

Performs j - i modulo 2pi, assuming less(i,j) is true.

Parameters:

j	any angle in [0:2pi[
i	any angle in [0:2pi[

Returns:

the value j - i, always positive.

Definition at line 184 of file AngleComputer.ih.

References M_PI.

{
  return ( i <= j ) ? j - i : j + (float)(M_PI*2.0) - i;
}

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

• AngleComputer.h
• AngleComputer.ih