chrono::ChFunctionInterp Class Reference

Description

Interpolation function.

Linear interpolation y=f(x) given a list of points (x,y).

#include <ChFunctionInterp.h>

Inheritance diagram for chrono::ChFunctionInterp:
Collaboration diagram for chrono::ChFunctionInterp:

Public Member Functions

 ChFunctionInterp (const ChFunctionInterp &other)
 
virtual ChFunctionInterpClone () 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 AddPoint (double x, double y, bool overwrite_if_existing=false)
 Add a point to the table. More...
 
void Reset ()
 
const std::map< double, double > & GetTable ()
 Retrieve the underlying table of points.
 
double GetStart () const
 Return the smallest value of x in the table.
 
double GetEnd () const
 Return the biggest value of x in the table.
 
double GetMax () const
 Return the maximum function value in the table.
 
double GetMin () const
 Return the minimum function value in the table.
 
void SetExtrapolate (bool extrapolate)
 Enable linear extrapolation. More...
 
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 double GetWeight (double x) const
 Return the weight of the function. 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.
 

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

◆ AddPoint()

void chrono::ChFunctionInterp::AddPoint ( double  x,
double  y,
bool  overwrite_if_existing = false 
)

Add a point to the table.

By default, adding a point with an x value that already exists in the table will lead to an exception. If overwrite_if_existing is set to true, the existing point will be overwritten instead.

◆ GetDer()

double chrono::ChFunctionInterp::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::ChFunctionInterp::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.

◆ GetVal()

double chrono::ChFunctionInterp::GetVal ( double  x) const
overridevirtual

Return the function output for input x.

Must be overridden by specialized classes.

Implements chrono::ChFunction.

◆ SetExtrapolate()

void chrono::ChFunctionInterp::SetExtrapolate ( bool  extrapolate)
inline

Enable linear extrapolation.

If enabled, the function will return linear extrapolation for x values outside the domain. while the first derivative will be kept equal to the derivative of the nearest two points. Second derivative in any case will be computed numerically based on first derivative.


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