/*
 *  =====================================================================
 *  Dynamically allocate, print, and add three-dimensional vectors
 *
 *  Copyright (C) 1998 by Mark Austin and David Chancogne.
 *                                                                     
 *  This software is provided "as is" without express or implied warranty.
 *  Permission is granted to use this software on any computer system,
 *  and to redistribute it freely, subject to the following restrictions:
 * 
 *  1. The authors are not responsible for the consequences of use of
 *     this software, even if they arise from defects in the software.
 *  2. The origin of this software must not be misrepresented, either
 *     by explicit claim or by omission.
 *  3. Altered versions must be plainly marked as such, and must not
 *     be misrepresented as being the original software.
 *  4. This notice is to remain intact.
 * 
 *  Written by : Mark Austin 
 *  =====================================================================
 */

#include <stdio.h>
#include "miscellaneous.h"

/* Declarations for vector functions */

void   vecPrint( char *, float *, int );
float *vecAdd( float *, float *, int );

int main( void ) {
enum { VectorLength = 3 };
float *fpA, *fpB, *fpC;

  /* [a] : Allocate and initialize vectors "A" and "B" */

  fpA = (float *) safeCalloc( VectorLength, sizeof(float) ,
                              __FILE__, __LINE__ );

  fpA [0] =  1; fpA [1] = 2; fpA [2] = 3;

  fpB = (float *) safeCalloc( VectorLength, sizeof(float) ,
                              __FILE__, __LINE__ );

  fpB [0] = -3; fpB [1] = 4; fpB [2] = 5;

  /* [b] : Compute "A + B" */

  fpC = vecAdd( fpA, fpB , VectorLength );

  /* [c] : Print contents of vectors */

  vecPrint( "A",   fpA , VectorLength );
  vecPrint( "B",   fpB , VectorLength );
  vecPrint( "A+B", fpC , VectorLength );

  /* [d] : Free vector memory */

  free ( fpA );
  free ( fpB );
  free ( fpC );
}

/*
 *  ================================================================
 *  vecAdd() : Addition of two vectors.
 * 
 *  Input :   float  *fpA -- pointer to float array.
 *            float  *fpB -- pointer to float array.
 *            int iLength -- length of float array.
 *  Output :  float *fpC  -- pointer to array containing vector sum.
 *  ================================================================
 */

float *vecAdd( float *fpA, float *fpB, int iLength ) {
float *fpC;
int   iRow;

     fpC = (float *) safeCalloc( iLength, sizeof(float) ,
                                 __FILE__, __LINE__ );

     for(iRow = 0 ; iRow < iLength; iRow++ )
         fpC [ iRow ] = fpA [ iRow ] + fpB [ iRow ];

     return ( fpC );
}

/* 
 *  =======================================================
 *  vecPrint() : Naive implementation of vector print.
 *  
 *  Input :   char *cpMessage -- pointer to vector message.
 *            float *fpVector -- pointer to float array.
 *            int     iLength -- length of float array.
 *  Output :  void.
 *  =======================================================
 */

void vecPrint( char *cpMessage , float *fpVector , int iLength ) {
int iRow;

    if(cpMessage != (char *) NULL) 
       printf("\nVECTOR \"%s\" \n\n", cpMessage );
    else 
       printf("\nVECTOR : \"UNTITLED\" \n\n");

    for(iRow = 1; iRow <= iLength; iRow++) 
       printf(" %3d   %16.5e\n", iRow, fpVector[ iRow-1 ]);

}