Click or drag to resize
CsPeriodic Class
Extension of the Spline class to interpolate data points with periodic boundary conditions.
Inheritance Hierarchy

Namespace: Imsl.Math
Assembly: ImslCS (in ImslCS.dll) Version: 6.5.2.0
Syntax
[SerializableAttribute]
public class CsPeriodic : Spline

The CsPeriodic type exposes the following members.

Constructors
  NameDescription
Public methodCsPeriodic
Constructs a cubic spline that interpolates the given data points with periodic boundary conditions.
Top
Methods
  NameDescription
Public methodDerivative(Double)
Returns the value of the first derivative of the spline at a point.
(Inherited from Spline.)
Public methodDerivative(Double, Int32)
Returns the value of the derivative of the spline at a point.
(Inherited from Spline.)
Public methodDerivative(Double, Int32)
Returns the value of the derivative of the spline at each point of an array.
(Inherited from Spline.)
Public methodEquals
Determines whether the specified object is equal to the current object.
(Inherited from Object.)
Public methodEval(Double)
Returns the value of the spline at a point.
(Inherited from Spline.)
Public methodEval(Double)
Returns the value of the spline at each point of an array.
(Inherited from Spline.)
Protected methodFinalize
Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.
(Inherited from Object.)
Public methodGetBreakpoints
Returns a copy of the breakpoints.
(Inherited from Spline.)
Public methodGetHashCode
Serves as a hash function for a particular type.
(Inherited from Object.)
Public methodGetType
Gets the Type of the current instance.
(Inherited from Object.)
Public methodIntegral
Returns the value of an integral of the spline.
(Inherited from Spline.)
Protected methodMemberwiseClone
Creates a shallow copy of the current Object.
(Inherited from Object.)
Public methodToString
Returns a string that represents the current object.
(Inherited from Object.)
Top
Remarks

Class CsPeriodic computes a C^2 cubic spline interpolant to a set of data points (x_i, f_i) for i =0,\ldots n-1. The breakpoints of the spline are the abscissas. The program enforces periodic endpoint conditions. This means that the spline s satisfies s(a) = s(b), {\it{s'}}\left( {\it{a}} \right) = {\it{s'}}\left( {\it{b}} 
            \right), and s''\left( a \right) = s''\left( b 
            \right), where a is the leftmost abscissa and b is the rightmost abscissa. If the ordinate values corresponding to a and b are not equal, then a warning message is issued. The ordinate value at b is set equal to the ordinate value at a and the interpolant is computed.

If the data points arise from the values of a smooth (say C^4) periodic function f, i.e. f_i = f(x_i), then the error will behave in a predictable fashion. Let \xi be the breakpoint vector for the above spline interpolant. Then, the maximum absolute error satisfies


            |f-s|_{[\xi_0,\xi_{n-1}]} \le C |f^{(4)}|_{[{\xi_0 ,\xi_{n-1} }]} 
            |\xi|^4
where
|\xi|\;: = \max_{i=1,\ldots,n-1} |\xi_i - 
            \xi_{i - 1} |

For more details, see de Boor (1978, pages 320-322).

See Also

Reference

Other Resources