/***************************************************************************** * fixed.cpp        Blitz++ array using a custom type * $Id: fixed.cpp,v 1.6 2004/10/07 01:23:26 julianc Exp $ * This example illustrates how simple it is to create Blitz++ arrays * using a custom type.   *****************************************************************************/#include <blitz/array.h>BZ_USING_NAMESPACE(blitz)// A simple fixed point arithmetic class which represents a point// in the interval [0,1].class FixedPoint {public:    typedef unsigned int T_mantissa;    FixedPoint() { }    explicit FixedPoint(T_mantissa mantissa)    {          mantissa_ = mantissa;    }    FixedPoint(double value)    {        assert((value >= 0.0) && (value <= 1.0));        mantissa_ = T_mantissa(value * huge(T_mantissa()));    }       FixedPoint operator+(FixedPoint x)    { return FixedPoint(mantissa_ + x.mantissa_); }    double value() const    { return mantissa_ / double(huge(T_mantissa())); }private:    T_mantissa mantissa_;};ostream& operator<<(ostream& os, const FixedPoint& a){    os << a.value();    return os;}int main(){    // Now create an array using the FixedPoint class:    Array<FixedPoint, 2> A(4,4), B(4,4);    A = 0.5, 0.3, 0.8, 0.2,        0.1, 0.3, 0.2, 0.9,        0.0, 1.0, 0.7, 0.4,        0.2, 0.3, 0.8, 0.4;    B = A + 0.05;    cout << "B = " << B << endl;    return 0;}// Program output:// B = 4 x 4//      0.55      0.35      0.85      0.25//      0.15      0.35      0.25      0.95//      0.05      0.05      0.75      0.45//      0.25      0.35      0.85      0.45/* * Note: Just because Array<T,N> supports all possible operators doesn't * mean that a user-defined class has to.  You only need to define the  * operators you actually use on the array.  This works because the ISO/ANSI * draft standard forbids instantiation of unused member functions: * * [temp.inst, paragraph 7] * An implementation shall not implicitly instantiate  a  function,  non- * virtual  member  function,  class  or  member  template  that does not * require instantiation.  It is unspecified whether or not an  implemen- * tation implicitly instantiates a virtual member function that does not * require specialization. */