我收到了一个错误：
Complex.h|87|error: expected constructor, destructor, or type conversion before '&' token|
Complex.h|88|error: expected constructor, destructor, or type conversion before '&' token|
State.h|67|error: expected constructor, destructor, or type conversion before '&' token|
State.h|68|error: expected constructor, destructor, or type conversion before '&' token|
这是来自http://www.ma.rhul.ac.uk/quantum-trajectories
的图书馆我尝试使用gcc / codeblocks / mingw编译simple.cc文件。下面有两个代码块，分别是complex.h和state.h。
// Complex.h -*- C++ -*-
/*
Copyright (C) 1988 Free Software Foundation
written by Doug Lea (dl@rocky.oswego.edu)
This file is part of the GNU C++ Library. This library is free
software; you can redistribute it and/or modify it under the terms of
the GNU Library General Public License as published by the Free
Software Foundation; either version 2 of the License, or (at your
option) any later version. This library is distributed in the hope
that it will be useful, but WITHOUT ANY WARRANTY; without even the
implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
PURPOSE. See the GNU Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free Software
Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
*/
// Modified by rschack
#ifndef _Complex_hhh
#define _Complex_hhh 1
#include <iostream>
#include <cmath>
class Complex
{
public:
//protected:
double re;
double im;
double real() const;
double imag() const;
Complex();
Complex(const Complex& y);
Complex(double r, double i=0);
~Complex();
Complex& operator = (const Complex& y);
Complex& operator += (const Complex& y);
Complex& operator += (double y);
Complex& operator -= (const Complex& y);
Complex& operator -= (double y);
Complex& operator *= (const Complex& y);
Complex& operator *= (double y);
Complex& operator /= (const Complex& y);
Complex& operator /= (double y);
void error(const char* msg) const;
Complex& timesI ();
Complex& timesMinusI ();
};
// non-inline functions
double hypotenuse (double, double);
Complex operator / (const Complex& x, const Complex& y);
Complex operator / (const Complex& x, double y);
Complex operator / (double x, const Complex& y);
Complex cos(const Complex& x);
Complex sin(const Complex& x);
Complex cosh(const Complex& x);
Complex sinh(const Complex& x);
Complex exp(const Complex& x);
Complex log(const Complex& x);
Complex pow(const Complex& x, int p);
Complex pow(const Complex& x, const Complex& p);
Complex pow(const Complex& x, double y);
Complex sqrt(const Complex& x);
istream& operator >> (istream& s, Complex& x);
ostream& operator << (ostream& s, const Complex& x);
// inline members
inline double Complex::real() const { return re; }
inline double Complex::imag() const { return im; }
inline Complex::Complex() {}
inline Complex::Complex(const Complex& y) :re(y.real()), im(y.imag()) {}
inline Complex::Complex(double r, double i) :re(r), im(i) {}
inline Complex::~Complex() {}
inline Complex& Complex::operator = (const Complex& y)
{
re = y.real(); im = y.imag(); return *this;
}
inline Complex& Complex::operator += (const Complex& y)
{
re += y.real(); im += y.imag(); return *this;
}
inline Complex& Complex::operator += (double y)
{
re += y; return *this;
}
inline Complex& Complex::operator -= (const Complex& y)
{
re -= y.real(); im -= y.imag(); return *this;
}
inline Complex& Complex::operator -= (double y)
{
re -= y; return *this;
}
inline Complex& Complex::operator *= (const Complex& y)
{
double r = re * y.real() - im * y.imag();
im = re * y.imag() + im * y.real();
re = r;
return *this;
}
inline Complex& Complex::operator *= (double y)
{
re *= y; im *= y; return *this;
}
// functions
inline int operator == (const Complex& x, const Complex& y)
{
return x.real() == y.real() && x.imag() == y.imag();
}
inline int operator == (const Complex& x, double y)
{
return x.imag() == 0.0 && x.real() == y;
}
inline int operator != (const Complex& x, const Complex& y)
{
return x.real() != y.real() || x.imag() != y.imag();
}
inline int operator != (const Complex& x, double y)
{
return x.imag() != 0.0 || x.real() != y;
}
inline Complex operator - (const Complex& x)
{
return Complex(-x.real(), -x.imag());
}
inline Complex conj(const Complex& x)
{
return Complex(x.real(), -x.imag());
}
inline Complex operator + (const Complex& x, const Complex& y)
{
return Complex(x.real() + y.real(), x.imag() + y.imag());
}
inline Complex operator + (const Complex& x, double y)
{
return Complex(x.real() + y, x.imag());
}
inline Complex operator + (double x, const Complex& y)
{
return Complex(x + y.real(), y.imag());
}
inline Complex operator - (const Complex& x, const Complex& y)
{
return Complex(x.real() - y.real(), x.imag() - y.imag());
}
inline Complex operator - (const Complex& x, double y)
{
return Complex(x.real() - y, x.imag());
}
inline Complex operator - (double x, const Complex& y)
{
return Complex(x - y.real(), -y.imag());
}
inline Complex operator * (const Complex& x, const Complex& y)
{
return Complex(x.real() * y.real() - x.imag() * y.imag(),
x.real() * y.imag() + x.imag() * y.real());
}
inline Complex operator * (const Complex& x, double y)
{
return Complex(x.real() * y, x.imag() * y);
}
inline Complex operator * (double x, const Complex& y)
{
return Complex(x * y.real(), x * y.imag());
}
inline double real(const Complex& x)
{
return x.real();
}
inline double imag(const Complex& x)
{
return x.imag();
}
inline double abs(const Complex& x)
{
return hypotenuse(x.real(), x.imag());
}
inline double norm(const Complex& x)
{
return (x.real() * x.real() + x.imag() * x.imag());
}
inline double arg(const Complex& x)
{
return atan2(x.imag(), x.real());
}
inline Complex polar(double r, double t)
{
return Complex(r * cos(t), r * sin(t));
}
#endif //_Complex_hhh
// State.h -*- C++ -*- State algebra in Hilbert space.
//
// Copyright (C) 1995 Todd Brun and Ruediger Schack
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
//
// ----------------------------------------------------------------------
// If you improve the code or make additions to it, or if you have
// comments or suggestions, please contact us:
//
// Dr. Todd Brun Tel +44 (0)171 775 3292
// Department of Physics FAX +44 (0)181 981 9465
// Queen Mary and Westfield College email t.brun@qmw.ac.uk
// Mile End Road, London E1 4NS, UK
//
// Dr. Ruediger Schack Tel +44 (0)1784 443097
// Department of Mathematics FAX +44 (0)1784 430766
// Royal Holloway, University of London email r.schack@rhbnc.ac.uk
// Egham, Surrey TW20 0EX, UK
/////////////////////////////////////////////////////////////////////////////
#ifndef _State_hhh
#define _State_hhh 1
#include "Complex.h"
enum FreedomType{ ALL, FIELD, SPIN, ATOM };
// FreedomType lists the different types of physical systems specifically
// recognized by this program; more may be added if necessary.
// FIELD is an oscillator degree of freedom, which is described in the
// Fock state or Excited Coherent State basis;
// SPIN is a spin 1/2 or two-level atom;
// ATOM is an atom or N-level system;
// ALL leaves the physical type of system unspecified.
// Note that certain member functions will only work for degrees of freedom
// of a particular type.
enum ImaginaryUnit{ IMAGINARY_UNIT, MINUS_IMAGINARY_UNIT };
const ImaginaryUnit IM = IMAGINARY_UNIT;
const ImaginaryUnit M_IM = MINUS_IMAGINARY_UNIT;
// For efficiency, special routines have been included allowing States
// and Operators to be multiplied by i and -i without invoking the full
// Complex arithmetic. Note that multiplication by ImaginaryUnit is
// define ONLY for States and Operators; 3*IM is not a legal
// expression.
#ifndef NON_GNU_PROTOTYPE
class PrimaryOperator;
#else
extern class PrimaryOperator;
#endif
// I/O functions for FreedomType
ostream& operator<<( ostream&, FreedomType );
istream& operator>>( istream&, FreedomType& );
class State{
// The State class represents quantum states in a particular choice of
// Hilbert space; this can include varying numbers of physical degrees
// of freedom, described by varying numbers of basis states.
public: // public functions
// constructors and destructors
State();
// Default constructor; produces a State of size 0.
State(const State& state);
// Copy constructor.
State(int n, FreedomType form=FIELD);
// Produces a single degree-of-freedom State with n basis states;
// all basis states have amplitude 0 except the ground state,
// which has amplitude 1; form gives the FreedomType of the State
// (default is FIELD).
State(int n, int* dimensions, FreedomType* forms);
// Multiple degree of freedom ground State. n gives the number of
// degrees of freedom; dimensions is an array of n integers, which
// specify the number of basis states to allocate for each degree
// of freedom; forms is an array of n FreedomTypes, giving the
// physical type of each degree of freedom. The basis of the full
// n-freedom state is given by the products of the basis states of
// the n freedoms; all have amplitude 0 except for the ground state.
State(int n, Complex* elements, FreedomType form=FIELD);
// Produces a one degree-of-freedom State with n basis
// states. elements is an array of n Complex numbers, representing
// the amplitudes of the n basis states; form gives the FreedomType
// of the State (default is FIELD).
State(int n, int nstate, FreedomType form=FIELD); // Fock state
// Produces a single degree-of-freedom State with n basis states;
// all basis states have amplitude 0 except state number nstate,
// which has amplitude 1; form gives the FreedomType of the State
// (default is FIELD).
State(int n, Complex alpha, FreedomType form=FIELD); // Coherent state
// Produces a one degree-of-freedom State with n basis
// states in a coherent state given by the Complex number alpha.
// The State is represented in a Fock (number) state basis.
// form gives the FreedomType of the State (default is FIELD).
State(int n, int nstate, Complex alpha, FreedomType form=FIELD);
// Excited coherent state. Produces a single degree-of-freedom State
// with n basis states. Basis state number nstate has amplitude 1,
// all others have amplitude 0, and the state is in the excited coherent
// state or displaced Fock state basis, centered at alpha in phase space.
// form gives the FreedomType of the State (default is FIELD).
State(int n, State* stateList); // Product state
// Produces an n degree-of-freedom state. stateList is an array of
// n one-freedom states. The n-freedom state will be produced in a
// product state of the n states in stateList. The FreedomTypes and
// dimensions of the different freedoms of the n-freedom state will
// match those of the one-freedom states in stateList.
~State(); // destructor
// public functions used by constructors and destructors
void fock(int n, int nstate); // create a Fock state
void coherent(int n, Complex alpha); // create a Coherent state
void productState(int n, State* stateList); // create a product state
// Member arithmetic operations
inline Complex& operator[](int n) { // subscript operator; gives
if( nSkip != 1 ) // access to the amplitude
return myPointer[nSkip*n]; // of the nth basis state
else // Note that this amplitude
return myPointer[n]; // can be changed as well as
}; // read. Usage: psi[n]
// Note the presence of nSkip;
// this is part of the
// SkipVector structure, used
// for multiple freedom states
Complex elem(const int*) const;
// MultiDim subscripting; takes as an argument an array of integers
// of length equal to the number of degrees of freedom. Returns
// the amplitude of the corresponding basis state. Note that this
// subscripting is read-only. Usage: psi.elem(n_array)
Complex& operator[](int*);
// same as elem (above), but also permits the amplitudes to be
// changed. Usage: psi[n_array]
State& operator=(const State&); // assignment
State& operator=(int);
// zero assignment; enables one to type psi=0 to set all amplitudes
// to 0. Gives an error for any int other than 0.
Complex operator*(const State&) const; // inner product
State& operator*=(const Complex&); // multiply by Complex scalar
State& operator*=(double); // multiply by real scalar
State& operator*=(ImaginaryUnit); // multiply by ImaginaryUnit
State& operator+=(const State&); // add a State
State& operator-=(const State&); // subtract State
// Friend arithmetic operations
friend State operator*(const Complex&, const State&);
// multiply a State by a Complex scalar: z*psi
friend State operator*(const State&, const Complex&);
// multiply a State by a Complex scalar (other order): psi*z
friend State operator*(double, const State&);
// multiply a State by a real scalar: x*psi
friend State operator*(const State&, double);
// multiply a State by a real scalar (other order): psi*x
friend State operator*(ImaginaryUnit, const State&);
// multiply a State by an ImaginaryUnit (i or -i)
friend State operator*(const State&, ImaginaryUnit);
// multiply a State by an ImaginaryUnit (i or -i) (other order)
friend State operator+(const State&, const State&);
// add two States
friend State operator-(const State&, const State&);
// subtract one State from another
friend State operator+(const State&); // unary +
friend State operator-(const State&); // unary -
// Friend I/O operations
friend ostream& operator<<( ostream&, const State&);
// outputs a state in a standard ASCII form. This can be used to
// save and recover results of a calculation.
friend istream& operator>>( istream&, State& );
// inputs a state in a standard ASCII form. This can be used to
// save and recover results of a calculation.
// Information-returning and utility member functions
void xerox(const State& a);
// make MINIMAL copy of State (for use in temps). Improves efficiency
// when dynamical allocation of basis states is being used. Chiefly
// used by the Operator class; should not be needed by ordinary users.
// For an explanation of the dynamical allocation see adjustCutoff
// below.
int size(); // length of data array
int getSize(int = 0); // size of nth degree of freedom
void diagnostic(); // debugging info
void normalize(); // normalize state, i.e., psi*psi = 1
// Member functions accessing coordinates; for a full explanation of
// this, see the basis-changing member functions below.
Complex centerCoords();
// return center of coordinates
Complex getCoords(int = 0);
// center of coordinates of nth freedom (default 0)
void setCoords(Complex&,int=0);
// set the value of the coords for a freedom (default 0)
void displaceCoords(Complex&, int=0);
// adds a Complex displacement to the center of
// coordinates of a freedom (default freedom is 0)
double checkBounds(int, int=2);
// check amplitudes of top basis states
// (default: top 2 basis states)
// Basis-changing member functions
// This QSD library makes use of the localization property to greatly
// improve the efficiency of calculations. In QSD, for a wide variety
// of problems, field states tend towards highly localized wavepackets
// in phase space. These wave packets are closely centered on some point
// alpha (a Complex number) which is given by the expectation value
// alpha = <a>, where a is the harmonic oscillator annihilation operator.
//
// If alpha is large, it requires a great many ordinary Fock states to
// represent such a wavepacket; the number of Fock states n goes like
// |alpha|^2. By choosing a different set of basis states an enormous
// savings is possible.
//
// We use the excited coherent state basis |alpha,n> to represent our
// states, choosing alpha=<a> for maximum efficiency. (Ordinary Fock
// states would correspond to alpha=0.) As the value of <a> will change
// with time, the basis must also be changed fairly often. This adds to
// the cost of a calculation; but the savings from the moving basis
// far outweigh this added complexity.
//
// Note that this only applies to freedoms of type FIELD. For multiple
// degree-of-freedom states, each FIELD degree of freedom can be moved
// separately. Trying to move the basis of a non-FIELD freedom will
// produce an error.
//
// Note also that the user is not required to use the moving basis. For
// problems without strong localization, the moving basis adds to the
// computational overhead while producing little benefit, and should not
// be invoked.
//
// For further details, see J. Phys. A 28, 5401-5413 (1995).
void moveCoords(const Complex& displacement, int theFreedom=0,
double shiftAccuracy=1e-4);
// Relative shift of the center of coordinates. displacement
// gives the amount by which to shift alpha, theFreedom indicates
// which degree of freedom is to be shifted. shiftAccuracy
// gives the accuracy with which to make the shift
// (default 1e-4). The physical state is unchanged, but it is
// represented in a new basis |alpha+displacement,n>
// Uses private moveStep member function.
void recenter(int theFreedom=0,double shiftAccuracy=1e-4);
// Recenters freedom theFreedom at its expectation value in phase space.
// The physical state is unchanged, but is represented in a new
// basis |<a>,n>, a being the annihilation operator for the
// selected degree of freedom. Uses moveCoords.
void moveToCoords(const Complex& alpha, int theFreedom=0,
double shiftAccuracy=1e-4);
// Like moveCoords, but instead of shifting by a Complex displacement
// it moves the basis to a new absolute position alpha in phase space.
// Uses moveCoords.
void centerOn(State& psi,double shiftAccuracy=1e-4);
// Leaves the physical state unchanged, but represents it in the
// same basis as the given state psi. Uses moveCoords. Can be used
// with multiple degree-of-freedom states, though the states must
// have the same number and type of freedoms; it will change the
// basis only of the FIELD degrees of freedom.
// Cutoff-adjusting member functions
// For efficiency, it is possible to restrict the number of basis vectors
// actually used by including only those with amplitudes appreciably
// greater than zero. The criterion used is based on two parameters:
// epsilon and padSize. All of the top states of a freedom whose total
// probability is less than epsilon are excluded except for a number of
// "buffer" basis states, or "pad", equal to padSize. If the "pad" begins
// to gain appreciable probability (i.e., probability over epsilon) the
// number of basis states can be dynamically increased. In this way,
// no more basis states are used than are necessary. This is particularly
// useful in conjunction with the moving basis.
void adjustCutoff(int theFreedom=0, double epsilon=1e-4, int padSize=2);
// adjust amount of storage used by the State by adjusting the
// cutoff for freedom number theFreedom.
void fullSize(); // makes size of state match physical size of storage
private: // private data and functionss
// SkipVector part -- used to act on single degree of freedom in memory
//
// The QSD code assumes that all Operators are defined in terms of Primary
// Operators which act on a single degree of freedom. In order for this
// to work successfully, it must be possible to loop over a single degree
// of freedom, leaving all the others unchanged. This is embodied in the
// notion of a SkipVector -- a data structure which is treated like an
// ordinary array, but steps through memory by an ``skip'' larger than one.
Complex* myPointer; // pointer to storage
int mySize; // array size
int nSkip; // steps between elements (the ``skip'')
// One dimensional state part --
// used for greater efficiency in 1 Freedom problems
int totalDim; // total number of elements
int maxSize; // number of elements actually used
FreedomType myType; // type of freedom
Complex* data; // element storage; this points to an array
// of complex numbers giving the amplitudes
// of the basis states
Complex coord; // center of coordinates in phase space
// (see the moving basis, above)
// MultiState part -- used for >1 degrees of freedom
//
// The basis states for a multiple-degree-of-freedom state are the
// products of the basis states of the individual degrees of freedom
// which make up the total state. If there are n_i basis states to
// represent the ith degree of freedom, then a particular basis state
// of the total state is given by indices {i_0,...,i_N} for an N+1 freedom
// state.
//
// The amplitudes for these basis states are stored in the array data,
// just as for single degree-of-freedom states. The amplitude for the
// basis state {i_0,...,i_N} is stored at the location
//
// loc = i_0 + i_1*n_0 + i_2*n_0*n_1 + ... + i_N*n_0*...*n_(N-1).
//
// where i_m ranges from 0 to n_m-1.
//
// Incrementing the mth index by 1 is equivalent to stepping through
// the data array by an amount
//
// nSkips[m] = n_0*n_1*...*n_(m-1).
int nFreedoms; // number of degrees of freedom
int* nDims; // number of dimensions (basis states)
// for each freedom
int* sizes; // number of dimensions (basis states)
// actually used by each freedom
int* nSkips; // index spacing in data field of ith freedom
int* partDims; // subspace dim of first i freedoms
FreedomType* freedomTypes; // types of degrees of freedom (FIELD, SPIN, etc.)
Complex* coords; // centers of coordinates in phase space
// Private member functions
void apply(PrimaryOperator&, int, int, FreedomType, double);
// apply a PrimaryOperator to a State
void copy(const State&); // copy a state
void free(); // recycle storage
void moveStep(Complex&, Complex&); // shift coords by infinitesimal step
void stretchFreedom(int,int); // increase storage used by a freedom
void shrinkFreedom(int,int); // compact storage used by a freedom
void error(const char*) const; // print out error message and exit
friend class Operator; // friend class
};
#endif
答案 0 :(得分：3)
旧代码，应该是
std::istream& operator >> (std::istream& s, Complex& x);
std::ostream& operator << (std::ostream& s, const Complex& x);
您的编译器可能有选项链接不需要std ::前缀的头文件和库，但可能更好地编辑代码。
答案 1 :(得分：1)
好吧，鉴于它似乎在抱怨istream和ostream，而你有include <iostream>，我首先要看看你是否有using namespace std;。
如果没有，您可以添加它，但最好明确引用std命名空间，例如：
std::istream& operator >> (std::istream& s, Complex& x);
如果您真的没有选择通过std::为所有内容添加前缀，那么using namespace std可能是最简单的选项。
答案 2 :(得分：-2)
“operator”和符号之间有空格：
operator >>
而不是
operator>>
在整个代码中看起来这是一种特有的，所以你需要对它进行查找替换。