Description

Sequence function: y = sequence_of_functions(f1(y), f2(y), f3(y)) All other function types can be inserted into this.

#include <ChFunctionSequence.h>

Inheritance diagram for chrono::ChFunctionSequence:

Collaboration diagram for chrono::ChFunctionSequence:

Public Member Functions
	ChFunctionSequence (const ChFunctionSequence &other)

virtual ChFunctionSequence *	Clone () const override
	"Virtual" copy constructor (covariant return type).

virtual Type	GetType () const override
	Return the unique function type identifier.

virtual double	GetVal (double x) const override
	Return the function output for input x. More...

virtual double	GetDer (double x) const override
	Return the first derivative of the function. More...

virtual double	GetDer2 (double x) const override
	Return the second derivative of the function. More...

void	SetStartArg (double start)
	The sequence of functions starts at this x value.

double	GetStartArg () const
	The sequence of functions starts at this x value.

std::list< ChFseqNode > &	GetFunctions ()
	Access the list of the sub-functions.

void	Setup ()
	Scans all the seq.of functions and setup the timings and continuity offsets, to satisfy all constraints. More...

bool	InsertFunct (std::shared_ptr< ChFunction > myfx, double duration, double weight=1, bool c0=false, bool c1=false, bool c2=false, int position=-1)
	Insert function after the fx with defined "position" index in list. More...

bool	RemoveFunct (int index)
	Remove and deletes function with defined "position", and returns true. More...

std::shared_ptr< ChFunction >	GetFunction (int index)
	Returns the ChFunction with given "index". More...

ChFseqNode *	GetNode (int index)
	As above, but returns the function node (containing function pointer, function duration, continuity flags with previous node, etc.)

double	GetWidth (int index)
	As above, but returning duration. More...

virtual double	GetWeight (double x) const override
	Return the weight of the function. More...

void	SetClamped (bool clamped)
	Clamp end return value of sequence to last node value.

bool	IsClamped () const
	Get if sequence end return value is clamped.

virtual void	ArchiveOut (ChArchiveOut &archive_out) override
	Method to allow serialization of transient data to archives.

virtual void	ArchiveIn (ChArchiveIn &archive_in) override
	Method to allow de-serialization of transient data from archives.

Public Member Functions inherited from chrono::ChFunction
	ChFunction (const ChFunction &other)

virtual double	GetDer3 (double x) const
	Return the third derivative of the function. More...

virtual double	GetDerN (double x, int der_order) const
	Return the Nth derivative of the function (up to 3rd derivative). More...

virtual void	Update (double x)
	Update the function at the provided value of its argument.

virtual double	GetMax (double xmin, double xmax, double sampling_step, int der_order) const
	Estimate the maximum of the function (or its der_order derivative) in the range [xmin, xmax]. More...

virtual double	GetMin (double xmin, double xmax, double sampling_step, int der_order) const
	Estimate the minimum of the function (or its der_order derivative) in the range [xmin, xmax]. More...

virtual double	GetMean (double xmin, double xmax, double sampling_step, int der_order) const
	Estimate the mean of the function (or its der_order derivative) in the range [xmin, xmax]. More...

virtual double	GetSquaredMean (double xmin, double xmax, double sampling_step, int der_order) const
	Estimate the squared mean of the function (or its der_order derivative) in the range [xmin, xmax]. More...

virtual double	GetIntegral (double xmin, double xmax, double sampling_step, int der_order) const
	Estimate the integral of the function (or its der_order derivative) over the range [xmin, xmax]. More...

virtual double	GetPositiveAccelerationCoeff () const
	Compute the positive acceleration coefficient. More...

virtual double	GetNegativeAccelerationCoeff () const
	Compute the negative acceleration coefficient. More...

virtual double	GetVelocityCoefficient () const
	Compute the velocity coefficient. More...

virtual void	OutputToASCIIFile (std::ostream &file, double xmin, double xmax, int samples, char delimiter)
	Store X-Y pairs to an ASCII File. More...

virtual ChMatrixDynamic	SampleUpToDerN (double xmin, double xmax, double step, int derN=0)
	Sample function on given interval [xmin, xmax], up to derN derivative (0 being the function ouput itself). More...

double	operator() (double arg) const
	Alias operator of the GetVal function.

Protected Attributes
std::list< ChFseqNode >	m_functions
	the list of sub functions

double	m_start
	start time for sequence

bool	m_clamped
	trigger end value clamp

Additional Inherited Members
Public Types inherited from chrono::ChFunction
enum	Type { BSPLINE, CONSTANT, CONSTACC, CONSTJERK, CUSTOM, CYCLOIDAL, DERIVATIVE, FILLET3, INTEGRAL, INTERP, LAMBDA, MIRROR, OPERATOR, POLY, POLY23, POLY345, RAMP, REPEAT, SEQUENCE, SINE, SINE_STEP }
	Enumeration of function types.

Member Function Documentation

◆ GetDer()

double chrono::ChFunctionSequence::GetDer ( double x ) const

overridevirtual

Return the first derivative of the function.

Default implementation computes a numerical differentiation. Inherited classes may override this method with a more efficient implementation (e.g. analytical solution).

Reimplemented from chrono::ChFunction.

◆ GetDer2()

double chrono::ChFunctionSequence::GetDer2 ( double x ) const

overridevirtual

Return the second derivative of the function.

Default implementation computes a numerical differentiation. Inherited classes may override this method with a more efficient implementation (e.g. analytical solution).

Reimplemented from chrono::ChFunction.

◆ GetFunction()

std::shared_ptr< ChFunction > chrono::ChFunctionSequence::GetFunction ( int index )

Returns the ChFunction with given "index".

If index = 0, returns always head (beginning),
If index = -1 returns tail (end).
If index > max number of current nodes, returns tail fx anyway.

◆ GetVal()

double chrono::ChFunctionSequence::GetVal ( double x ) const

overridevirtual

Return the function output for input x.

Must be overridden by specialized classes.

Implements chrono::ChFunction.

◆ GetWeight()

double chrono::ChFunctionSequence::GetWeight ( double x ) const

overridevirtual

Return the weight of the function.

(useful for applications where you need to mix different weighted ChFunctions)

Reimplemented from chrono::ChFunction.

◆ GetWidth()

double chrono::ChFunctionSequence::GetWidth ( int index )

As above, but returning duration.

(return value is reference, so it can be also changed later, but remember Setup() for the ChFunctionSequence after you modified this return value by reference TO DO). If no function, returns 0.

◆ InsertFunct()

bool chrono::ChFunctionSequence::InsertFunct	(	std::shared_ptr< ChFunction >	myfx,
		double	duration,
		double	weight = `1`,
		bool	c0 = `false`,
		bool	c1 = `false`,
		bool	c2 = `false`,
		int	position = `-1`
	)

Insert function after the fx with defined "position" index in list.

If index is higher than available objects, it simply goes to the end.
If index = 0 insert at the beginning,
If index = -1 insert at the end. Inserted functions will be deleted automatically when this object will be deleted. The fx segment has its own 'weight': use 1.0 for default, or different weights if you want that GetWeight() will give different results depending on the "x" parameter. Set c0=true if you want to force C0 continuity with previous function (an offset will be implicitly added to the function, as y=f(x)+Offset). Same for C1 and C2 continuity, using c1 and c2 flags.

Parameters

myfx	the function to insert
duration	duration of the time segment for this function
weight	optional weight scalar
c0	impose continuity to previous f() by offsetting/slanting
c1	impose continuity to previous f() by offsetting/slanting
c2	impose continuity to previous f() by offsetting/slanting
position	position index, 0,1,2,3.. (if -1 insert at the end)

◆ RemoveFunct()

bool chrono::ChFunctionSequence::RemoveFunct ( int index )

Remove and deletes function with defined "position", and returns true.

If index = 0, removes always head (beginning),
If index = -1 removes tail (end).
If index > max number of current nodes, removes tail anyway, but returns false.

◆ Setup()

void chrono::ChFunctionSequence::Setup ( )

Scans all the seq.of functions and setup the timings and continuity offsets, to satisfy all constraints.

This must be called whenever a new function is inserted, or its timing and continuity constraints are changed.

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

/builds/uwsbel/chrono/src/chrono/functions/ChFunctionSequence.h
/builds/uwsbel/chrono/src/chrono/functions/ChFunctionSequence.cpp

Description

Public Member Functions

Protected Attributes

Additional Inherited Members

Member Function Documentation

◆ GetDer()

◆ GetDer2()

◆ GetFunction()

◆ GetVal()

◆ GetWeight()

◆ GetWidth()

◆ InsertFunct()

◆ RemoveFunct()

◆ Setup()