// quantum computing emulation library
//
// R. Perry, Jan. 2018
//
#ifndef _QCE_H_
#define _QCE_H_

// macros:
//
//   DRAND	0.0 <= d < 1.0
//   IRAND	0 <= i < n
//
#define DRAND    (rand()/(RAND_MAX+1.0))
#define IRAND(n) ((unsigned long)(DRAND*(n)))
//
// print options:
//
#define PRINT_TANGLE -1 // entanglement measure
#define PRINT_LABELS  1 // decimal state labels
#define PRINT_BITS    2 // binary state indices and probabilities

// constants:
//
extern const double pi; // 4*atan(1)
extern const double s2; // sqrt(2)/2

// functions for real or complex states (see template.h and template.c):
//
//   Q		allocate a new state vector, uninitialized
//   zero	set state vector to all zeros
//   init	initialize state vector
//   swap	swap two states
//   product	tensor product
//   tangle	trace distance as a measure of entanglement
//   H		Hadamard transformation on one qubit
//   X		NOT transformation on one qubit
//   Z		phase-flip on one qubit
//   CX		controlled NOT on one qubit
//   M		measurement, uses DRAND
//   reduce	reduce state based on a measurement
//   collapse   collapse state based on a measurement of one qubit
//   operate	q = (a,b) -> (a,f(a,b,z))
//   print	display message and qubit state or entanglement measure
//   abs2	magnitude squared
//
// functions for complex only (see below):
//
//   Hra	Hadamard with non-resonant pulse error
//   Hrp	Hadamard with phase shift error
//   qfft	quantum FFT
//   fft	classical FFT
//
// general functions (see below):
//
//   SRAND	set srand() using time(0) or SRAND environment variable
//   printb	print in binary
//   error	print error message and exit
//   emalloc	malloc with exit on error
//
// typedefs:
//
//   Func	function type for operate()
//   qtype	complex or real amplitude
//   State	qubit register
//
typedef unsigned long (*Func) (unsigned long, unsigned long, unsigned long); 
//
typedef double qtype_Real;
typedef double _Complex qtype_Complex;
//
// concatenation for name construction in template.h and template.c:
//
#undef _namex_
#undef _name_
#define _namex_(x,y) x ## _ ## y
#define _name_(x,y) _namex_(x,y)  // x,y will be expanded in _namex_ if they are macros
//
// complex functions:
//
#undef QTYPE_COMPLEX
#define QTYPE_COMPLEX
#undef QTYPE
#undef qtype
#undef State
#define QTYPE Complex
#define qtype qtype_Complex
#define State State_Complex
#include "template.h"
//
// real functions:
//
#undef QTYPE_COMPLEX
#undef QTYPE
#undef qtype
#undef State
#define QTYPE Real
#define qtype qtype_Real
#define State State_Real
#include "template.h"
//
// type generic functions:
//
#undef QTYPE
#undef qtype
#undef State
#ifndef _QCE_C_ // not compiling qce.c
  #ifdef REAL
  #include "Real.h" 	// Real.h and Complex.h are temporary files 
  #else			//  generated by the Makefile
  #include "Complex.h"
  #endif
#endif
//
// functions for complex only:
//
void Hra( State_Complex q, unsigned int k, double ra);
void Hrp( State_Complex q, unsigned int k, double rp);
void qfft( State_Complex q, int inv);
void fft( double _Complex *X, unsigned long N, int inv);
//
// general functions:
//
unsigned int SRAND( void);
void printb( unsigned long x, unsigned int n);
void error( const char *msg);
void *emalloc( unsigned long size);

#endif // _QCE_H_