Description

Interface base class for scalar functions.

Base class for all Chrono scalar functions. The GetVal() and Clone() methods must be implemented by derived classes.

#include <ChFunctionBase.h>

Inheritance diagram for chrono::ChFunction:

Public Types

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.
 

Public Member Functions

 ChFunction (const ChFunction &other)
 
virtual ChFunctionClone () const =0
 "Virtual" copy constructor.
 
virtual Type GetType () const
 Return the unique function type identifier.
 
virtual double GetVal (double x) const =0
 Return the function output for input x. More...
 
virtual double GetDer (double x) const
 Return the first derivative of the function. More...
 
virtual double GetDer2 (double x) const
 Return the second derivative of the function. More...
 
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 double GetWeight (double x) const
 Return the weight of the function (useful for applications where you need to mix different weighted ChFunctions)
 
virtual void Update (double x)
 Update could be implemented by children classes, ex. to launch callbacks.
 
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], using sampling method.
 
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], using sampling method.
 
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], using sampling method.
 
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], using sampling method.
 
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], using sampling method.
 
virtual double GetPositiveAccelerationCoeff () const
 Computes the positive acceleration coefficient (inherited classes should override this).
 
virtual double GetNegativeAccelerationCoeff () const
 Compute the negative acceleration coefficient (inherited classes should override this).
 
virtual double GetVelocityCoefficient () const
 Compute the velocity coefficient (inherited classes must override this).
 
virtual int OutputToASCIIFile (std::ostream &file, double xmin=0, double xmax=1, int samples=200, 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.
 
virtual void ArchiveOut (ChArchiveOut &archive_out)
 Method to allow serialization of transient data to archives.
 
virtual void ArchiveIn (ChArchiveIn &archive_in)
 Method to allow de-serialization of transient data from archives. More...
 

Member Function Documentation

◆ ArchiveIn()

◆ GetDer()

double chrono::ChFunction::GetDer ( double  x) const
virtual

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 in chrono::ChFunctionConstJerk, chrono::ChFunctionBSpline, chrono::ChFunctionSequence, chrono::ChFunctionSetpoint, chrono::ChFunctionConstAcc, chrono::ChFunctionFillet3, chrono::ChFunctionInterp, chrono::ChFunctionPoly345, chrono::ChFunctionCycloidal, chrono::ChFunctionPoly23, chrono::ChFunctionSine, chrono::ChFunctionRamp, chrono::ChFunctionConst, chrono::ChFunctionPoly, and chrono::ChFunctionSineStep.

◆ GetDer2()

double chrono::ChFunction::GetDer2 ( double  x) const
virtual

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 in chrono::ChFunctionConstJerk, chrono::ChFunctionBSpline, chrono::ChFunctionSequence, chrono::ChFunctionSetpoint, chrono::ChFunctionConstAcc, chrono::ChFunctionFillet3, chrono::ChFunctionInterp, chrono::ChFunctionPoly345, chrono::ChFunctionCycloidal, chrono::ChFunctionPoly23, chrono::ChFunctionSine, chrono::ChFunctionConst, chrono::ChFunctionRamp, chrono::ChFunctionPoly, and chrono::ChFunctionSineStep.

◆ GetDer3()

double chrono::ChFunction::GetDer3 ( double  x) const
virtual

Return the third 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 in chrono::ChFunctionConstJerk, chrono::ChFunctionBSpline, chrono::ChFunctionCycloidal, and chrono::ChFunctionPoly345.

◆ GetDerN()

double chrono::ChFunction::GetDerN ( double  x,
int  der_order 
) const
virtual

Return the Nth derivative of the function (up to 3rd derivative).

Alias for other GetDerX functions.

◆ GetVal()

◆ OutputToASCIIFile()

int chrono::ChFunction::OutputToASCIIFile ( std::ostream &  file,
double  xmin = 0,
double  xmax = 1,
int  samples = 200,
char  delimiter = ',' 
)
virtual

Store X-Y pairs to an ASCII File.

Values are separated by delimiter (default=','). The function is sampled samples times, from xmin to xmax.

◆ SampleUpToDerN()

ChMatrixDynamic chrono::ChFunction::SampleUpToDerN ( double  xmin,
double  xmax,
double  step,
int  derN = 0 
)
virtual

Sample function on given interval [xmin, xmax], up to derN derivative (0 being the function ouput itself).

Store interval x=[xmin:step:xmax] and function evaluations as columns into matrix.


The documentation for this class was generated from the following files:
  • /builds/uwsbel/chrono/src/chrono/functions/ChFunctionBase.h
  • /builds/uwsbel/chrono/src/chrono/functions/ChFunctionBase.cpp