/*=========================================================================

  Program:   Visualization Toolkit
  Module:    vtkFunctionSet.h
  Language:  C++
  Date:      $Date$
  Version:   $Revision$


Copyright (c) 1993-2001 Ken Martin, Will Schroeder, Bill Lorensen 
All rights reserved.

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 * Redistributions of source code must retain the above copyright notice,
   this list of conditions and the following disclaimer.

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   this list of conditions and the following disclaimer in the documentation
   and/or other materials provided with the distribution.

 * Neither name of Ken Martin, Will Schroeder, or Bill Lorensen nor the names
   of any contributors may be used to endorse or promote products derived
   from this software without specific prior written permission.

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   misrepresented as being the original software.

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ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE FOR
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=========================================================================*/
// .NAME vtkFunctionSet - Abstract inteface for sets of functions
// .SECTION Description
// vtkFunctionSet specifies an abstract interface for set of functions
// of the form F_i = F_i(x_j) where F (with i=1..m) are the functions
// and x (with j=1..n) are the independent variables.
// The only supported operation is the  function evaluation at x_j.

// .SECTION See Also
// vtkImplicitDataSet vtkInterpolatedVelocityField 
// vtkInitialValueProblemSolver

#ifndef __vtkFunctionSet_h
#define __vtkFunctionSet_h

#include "vtkObject.h"

class VTK_COMMON_EXPORT vtkFunctionSet : public vtkObject
{
public:
  vtkTypeMacro(vtkFunctionSet,vtkObject);
  virtual void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // Evaluate functions at x_j.
  // x and f have to point to valid float arrays of appropriate 
  // sizes obtained with GetNumberOfFunctions() and
  // GetNumberOfIndependentVariables.
  virtual int FunctionValues(float* x, float* f) = 0;

  // Description:
  // Return the number of functions. Note that this is constant for 
  // a given type of set of functions and can not be changed at 
  // run time.
  virtual int GetNumberOfFunctions() { 
    return this->NumFuncs; }

  // Description:
  // Return the number of independent variables. Note that this is 
  // constant for a given type of set of functions and can not be changed  
  // at run time.
  virtual int GetNumberOfIndependentVariables() {
    return this->NumIndepVars; }

protected:
  vtkFunctionSet();
  ~vtkFunctionSet() {};

  int NumFuncs;
  int NumIndepVars;

private:
  vtkFunctionSet(const vtkFunctionSet&);  // Not implemented.
  void operator=(const vtkFunctionSet&);  // Not implemented.
};

#endif





