/***************************************************************************
 *		  Copyright (C) 1994  Charles P. Peterson                  *
 *	     4007 Enchanted Sun, San Antonio, Texas 78244-1254             *
 *              Email: Charles_P_Peterson@fcircus.sat.tx.us                *
 *                                                                         *
 *		  This is free software with NO WARRANTY.                  *
 *	      See gfft.c, or run program itself, for details.              *
 *		      Support is available for a fee.                      *
 ***************************************************************************
 *
 * Program:     gfft--General FFT analysis
 * File:        complex.h
 * Purpose:     define structs and ops for complex numbers
 * Author:      Charles Peterson (CPP)
 * History:     29-June-1993 CPP; Created.
 * Comment:     (1) C_MULT DOES NOT ALLOW INPUT & OUTPUT TO COINCIDE
 *              (2) MACROS DO NOT ASSUME float or double data size
 */

typedef struct {
float real;
float imaginary;
} Complex_float;

typedef struct {
double real;
double imaginary;
} Complex_double;


#ifndef NO_STRUCT_ASSIGN
#define CF_SWAP(a,b) {Complex_float tempc=(a); (a)=(b); (b)=tempc;}
#else
#define CF_SWAP(a,b) {\
		        float tempf;\
		        tempf = (a).real; \
		        (a).real = (b).real; \
		        (b).real = tempf; \
		        tempf = (a).imaginary; \
		        (a).imaginary = (b).imaginary; \
		        (b).imaginary = tempf; \
                   }
#endif


#define C_ADD(ADDEND, ADDENDUM, SUM) \
{ \
    (SUM).real = (ADDEND).real + (ADDENDUM).real; \
    (SUM).imaginary = (ADDEND).imaginary + (ADDENDUM).imaginary; \
}

#define C_SUB(MINUEND, SUBTRAHEND, DIFFERENCE) \
{ \
    (DIFFERENCE).real = (MINUEND).real - (SUBTRAHEND).real; \
    (DIFFERENCE).imaginary = (MINUEND).imaginary - (SUBTRAHEND).imaginary; \
}

#define C_MULT(MULTIPLICAND, MULTIPLIER, PRODUCT) \
{ \
    (PRODUCT).real = (MULTIPLICAND).real * (MULTIPLIER).real - \
      (MULTIPLICAND).imaginary * (MULTIPLIER).imaginary; \
    (PRODUCT).imaginary = (MULTIPLICAND).real * (MULTIPLIER).imaginary + \
      (MULTIPLICAND).imaginary * (MULTIPLIER).real; \
}

/*
 * And now, those prototypes involving complex numbers
 */
void cfft (Complex_float *datac, long n, int isign);
void rfft (Complex_float *datac, long n, int isign); /* input float array */