//   =====================< EXUTY.CPP >==============================
//   * UTILITY.CPP Examples					    *
//   * Description: Chapter 8                                       *
//   * Scientific C++ Building Numerical Libraries                  *
//   *                the Object-Oriented Way                       *
//   * by G. Buzzi-Ferraris                                         *
//   * Addison-Wesley (1993)                                        *
//   ****************************************************************
//   * To be assembled with UTILITY.OBJ				    *
//   ****************************************************************
//   * To execute: exuty <number> <file name > <Y/N>		    *
//   * If <number> equals a zero it executes all examples  	    *
//   * otherwise it executes only that example                 	    *
//   * It writes the results on < file name>                        *
//   * If not used it writes on screen                      	    *
//   * If one gives Y/N equal to Y it prints messages as well       *
//   * the default is Y                                       	    *
//   ****************************************************************
//   * Use:	exuty 0 pro.doc				            *
//   * Description:	Executes all examples			    *
//   * 	Prints the results on pro.doc			            *
//   * Use:	exuty 2 pro.doc n				    *
//   * Description:	Executes example 2			    *
//   * 	Prints the results on pro.doc			            *
//   * 	Does not print from Message			            *
//   * Use:	exuty						    *
//   * Description:	Executes all examples			    *
//   * 	Prints the results on stdout			            *
//   * Use:	exuty 3					            *
//   * Description:	Executes example 3			    *
//   ================================================================

//   ================================================================
//   *                         PROTOTYPES                    			*
//   ================================================================
void Ex_MachEps(void);
void Ex_MaxMin(void);
void Ex_Message(void);
void Ex_Sort(void);
void Ex_SqrtSumSqr(void);
void Ex_SumDot(void);
void Ex_Swap(void);
void Ex_TempFile(void);
void Ex_Error(void);

//   ================================================================
//   *                       include                        				*
//   ================================================================
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <math.h>

#include "utility.hpp"

//   ================================================================
//   *                         main                         				*
//   ================================================================
int main(int argc,char **argv)
{
const int NEXUTY = 9;
const int NMAX = NEXUTY + 1;
int i;
void (*ExUty[NMAX])(void);
char myfilename[81];
ExUty[1]=Ex_MachEps;
ExUty[2]=Ex_MaxMin;
ExUty[3]=Ex_Message;
ExUty[4]=Ex_Sort;
ExUty[5]=Ex_SqrtSumSqr;
ExUty[6]=Ex_SumDot;
ExUty[7]=Ex_Swap;
ExUty[8]=Ex_TempFile;
ExUty[NEXUTY]=Ex_Error;

if(argc>=3)
   {
   strcpy(myfilename,argv[2]);
   if((bzzFileOut=fopen(myfilename,"w"))==NULL)
      Error("fopen Failed in EXUTY");
   if(argc==4)bzzYesNo=toupper(argv[3][0]);
   }
else
   {
   bzzFileOut=stdout;
   }


if(argc==1||atoi(argv[1])<=0||atoi(argv[1])>NEXUTY)
   {     /* all examples */
   for(i=1;i<=NEXUTY;i++)
   (*ExUty[i])();
   }
else
   {
   (*ExUty[atoi(argv[1])])();
   }
return 0;
}
//   ================================================================
//   ====================   EXAMPLES   ==============================
//   ================================================================

//   ================================================================
//   ===================   MACH_EPS   ===============================
//   ================================================================
void Ex_MachEps(void)
  {
  Message
    ("\n\n\nMACH_EPS calculated and memorised %e",MACH_EPS);
  }

//   ================================================================
//   ====================   MAX_MIN   ===============================
//   ================================================================
void Ex_MaxMin(void)
{
   {
   Message("\n\n\n*** Examples of Max and Min ***\n");
   float a=-3.,b=-7.;
   double da=-3.,db=-7.;
   int ia=-3,ib=-7;
   Message("\n%f",Max(a,b));
   Message("\n%f",Min(a,b));
   Message("\n%f",Max(da,db));
   Message("\n%f",Min(da,db));
   Message("\n%d",Max(ia,ib));
   Message("\n%d",Min(ia,ib));

   Message("\n%f",MaxAbs(a,b));
   Message("\n%f",MinAbs(a,b));
   Message("\n%f",MaxAbs(da,db));
   Message("\n%f",MinAbs(da,db));
   Message("\n%d",MaxAbs(ia,ib));
   Message("\n%d",MinAbs(ia,ib));
   }
   {
   Message("\n\n\nMax Min of Array\n");
   float w[6]={-140.,5.,-1.,2.,3.,110.};
   float x;
   int im;
   x = Max(6,w);         Message("\n%f",x);
   x = Max(6,w,&im);     Message("\n%f %d",x,im);
   x = MaxAbs(6,w);      Message("\n%f",x);
   x = MaxAbs(6,w,&im);  Message("\n%f %d",x,im);
   x = Min(6,w);         Message("\n%f",x);
   x = Min(6,w,&im);     Message("\n%f %d",x,im);
   x = MinAbs(6,w);      Message("\n%f",x);
   x = MinAbs(6,w,&im);  Message("\n%f %d",x,im);
   }
} // end max min

//   ================================================================
//   ===================   MESSAGE   ================================
//   ================================================================
void Ex_Message(void)
   {
   Message("\n\n\n*** Example of Message ***\n");
   float f=3.14;
   int i=111;
   char a='A';
   Message("\nThis is a message\n");
   Message("float %f\tint %d\tchar %c\n",f,i,a);
   }

//   ================================================================
//   =====================   SORT   =================================
//   ================================================================
void Ex_Sort(void)
   {
   Message("\n\n\nFloat Sort \n");
   int n=10;
   float x[]={10.,3.,2.,1.,4.,5.,6.,8.,9.,7.};
   Sort(n,x);
   for(int i=0;i<n;i++)Message(" %f\n",x[i]);
   }

//   ================================================================
//   ==================   SqrtSumSqr   ==============================
//   ================================================================
void Ex_SqrtSumSqr(void)
{
   Message("\n\n****** SqrtSumSqr for float ******");
   {
   Message("\n\n*** First example: ***");
   Message("\nmany small coefficients and one large one\n");
   int i,n=5000;
   float x[5000];
   for(i=1;i<n;i++)x[i]=1.e-4;
   x[0] = 1.;
   float norm = SqrtSumSqr(n,x);
   Message("\n SqrtSumSqr  %.8e\n",norm);
   }
   {
   Message("\n\n*** Second example: ***");
   Message("\noverflow danger\n");
   int i,n = 100;
   float norm;
   float x[100];
   for(i = 0;i < n;i++)x[i]=BIG_FLOAT/20.;
   norm = SqrtSumSqr(n,x);
   Message("\n It must be %e\n",BIG_FLOAT/2.);
   Message("\n With SqrtSumSqr one obtains %e\n",norm);
   }
   {
   Message("\n\n*** Third example: ***");
   Message("\nunderflow for everything\n");
   int i,n=500;
   float x[500];
   for(i=0;i<n;i++)x[i]= TINY_FLOAT;
   float norm = SqrtSumSqr(n,x);
   Message("\n It must be %e\n",sqrt(500.)*TINY_FLOAT);
   Message("\n With SqrtSumSqr one obtains %e\n",norm);
   }
   Message("\n\n****** SqrtSumSqr for double ******");
   {
   Message("\n\n*** First example: ***");
   Message("\nmany small coefficients and one large one\n");
   int i,n=500;
   double x[500];
   for(i=1;i<n;i++)x[i]=1.e-8;
   x[0] = 1.;
   double norm;
   norm = SqrtSumSqr(sizeof(x)/sizeof(double),x);
   Message("\n%.16e",norm);
   }
   {
   Message("\n\n*** Second example: ***");
   Message("\noverflow danger\n");
   int i,n = 100;
   double norm;
   double x[100];
   for(i = 0;i < n;i++)x[i]=BIG_DOUBLE/20.;
   norm = SqrtSumSqr(n,x);
   Message("\n It must be %e\n",BIG_DOUBLE/2.);
   Message("\n With SqrtSumSqr one obtains %e\n",norm);
   }
   {
   Message("\n\n*** Third example: ***");
   Message("\nunderflow for everything\n");
   int i,n = 500;
   double norm;
   double x[500];
   for(i = 0;i < n;i++)x[i]=TINY_DOUBLE;
   norm = SqrtSumSqr(n,x);
   Message("\n Must be %e\n",sqrt(500.)*TINY_DOUBLE);
   Message("\n With SqrtSumSqr one obtains %e\n",norm);
   }

}

//   ================================================================
//   ==================   OPERATIONS   ==============================
//   ================================================================
void Ex_SumDot(void)
{
   Message("\n\n\n*** Examples of Sum ***\n");
   {
   Message("\n\nFirst example:\n");
   Message("Overflow control \n");
   int i,n=3;
   float x[3],y[3],z[3];
   x[0]=BIG_FLOAT;
   y[0]=BIG_FLOAT;
   x[1]=-BIG_FLOAT;
   y[1]=-BIG_FLOAT;
   x[2]=1.;
   y[2]=1.;
   Sum(n,x,y,z);
   for(i=0;i<n;i++)Message("\n%e",z[i]);
   }
   {
   Message("\n\nSecond example:\n");
   Message("with vector substitution\n");
   int i,n=3;
   float x[3],y[3];
   x[0]=BIG_FLOAT;
   y[0]=BIG_FLOAT;
   x[1]=-BIG_FLOAT;
   y[1]=-BIG_FLOAT;
   x[2]=1.;
   y[2]=1.;
   Sum(n,x,y);
   for(i=0;i<n;i++)Message("\n%e",x[i]);
   }
   {
   Message("\n\nThird example:\n");
   Message("with equal vectors\n");
   int i,n=3;
   float x[3];
   x[0]=1.;
   x[1]=2.;
   x[2]=3.;
   Sum(n,x);
   for(i=0;i<n;i++)Message("\n%e",x[i]);
   }
   Message("\n\n\n*** Examples of Difference ***\n");
   {
   Message("\n\nFirst example:\n");
   Message("With overflow control \n");
   int i,n=3;
   float x[3],y[3],z[3];
   x[0]=BIG_FLOAT;
   y[0]=-BIG_FLOAT;
   x[1]=15.;
   y[1]=BIG_FLOAT;
   x[2]=1.;
   y[2]=1.;
   Difference(n,x,y,z);
   for(i=0;i<n;i++)Message("\n%e",z[i]);
   }
   {
   Message("\n\nSecond example:\n");
   Message("with overlap\n");
   int i,n=3;
   float x[3],y[3];
   x[0]=BIG_FLOAT;
   y[0]=-BIG_FLOAT;
   x[1]=15.;
   y[1]=BIG_FLOAT;
   x[2]=1.;
   y[2]=1.;
   Difference(n,x,y);
   for(i=0;i<n;i++)Message("\n%e",x[i]);
   }
   {
   Message("\n\nThird example:\n");
   Message("\nDifference y = x - y = 2,0,0\n");
   int i,n=3;
   float x[3],y[3];
   x[0]=1.;
   y[0]=-1.;
   x[1]=2.;
   y[1]=2.;
   x[2]=1.;
   y[2]=1.;
   Difference(n,x,y,1);
   for(i=0;i<n;i++)Message("\n%e",y[i]);
   }
   Message("\n\n\n*** Examples of Dot ***\n");
   {
   Message("\n\nFirst example:\n");
   int i,n=3;
   float x[3],y[3];
   x[0]=1.;
   y[0]=1.;
   x[1]=2.;
   y[1]=2.;
   x[2]=3.;
   y[2]=3.;
   float result = Dot(n,x,y);
   Message("\n%e",result);
   }
   {
   Message("\n\nSecond example:\n");
   Message("\noverflow danger\n");
   int i,n=3;
   float x[3],y[3];
   x[0]=BIG_FLOAT;
   y[0]=BIG_FLOAT;
   x[1]=2.;
   y[1]=2.;
   x[2]=1.;
   y[2]=1.;
   float result = Dot(n,x,y);
   Message("\n%e",result);
   }
   {
   Message("\n\nThird example:\n");
   Message("\noverflow danger\n");
   int i,n=3;
   float x[3],y[3];
   x[0]=1.;
   y[0]=1.;
   x[1]=-BIG_FLOAT;
   y[1]=BIG_FLOAT;
   x[2]=3.;
   y[2]=3.;
   float result = Dot(n,x,y);
   Message("\n%e",result);
   }
   Message("\n\n\nExamples of Product\n");
   {
   Message("\n\nFirst example:\n");
   Message("\noverflow danger\n");
   float v[]={1.,2.,3.,BIG_FLOAT,5.,6.};
   float c=3.;
   float r[6];
   Product(6,c,v,r);
   for(int i=0;i < 6;i++)   Message("\n%e",r[i]);
   }
   {
   Message("\n\nSecond example:\n");
   Message("\nProduct only on two elements of six\n");
   float v[]={1.,2.,3.,4.,5.,6.};
   float c=3.;
   Product(2,c,v+2);
   for(int i=0;i<6;i++)   Message("\n%e",v[i]);
   }
   {
   Message("\n\nThird example:\n");
   Message("\nresult in overlap\n");
   float v[]={1.,2.,3.,BIG_FLOAT,5.,6.};
   float c=3.;
   Product(6,c,v);
   for(int i=0;i<6;i++)   Message("\n%e",v[i]);
   }
   Message("\n\n\nExamples of Division\n");
   {
   Message("\n\nFirst example:\n");
   Message("\noverflow control\n");
   float v[]={TINY_FLOAT,2.,3.,BIG_FLOAT,5.,6.};
   float c=TINY_FLOAT;
   float r[6];
   Division(6,v,c,r);
   for(int i=0;i<6;i++)   Message("\n%e",r[i]);
   }
   {
   Message("\n\nSecond example:\n");
   Message("\nDivision for two elements on six\n");
   float v[]={1.,2.,3.,4.,5.,6.};
   float c=3.;
   Division(2,v+2,c);
   for(int i=0;i<6;i++)   Message("\n%e",v[i]);
   }
   {
   Message("\n\nThird example:\n");
   Message("\nwith substitution\n");
   float v[]={1.,2.,3.,BIG_FLOAT,5.,6.};
   float c=3.;
   Division(6,v,c);
   for(int i=0;i<6;i++)   Message("\n%e",v[i]);
   }
   {
   Message("\n\nFourth example:\n");
   Message("\noverflow danger\n");
   float v[]={TINY_FLOAT,2.,3.,BIG_FLOAT,5.,6.};
   float c=TINY_FLOAT;
   float r[6];
   Division(6,v,c,r);
   for(int i=0;i<6;i++)   Message("\n%e",r[i]);
   }
   {
   Message("\n\nFifth example:\n");
   Message("\nDivision by 0 \n");
   float v[]={1.,2.,3.,BIG_FLOAT,5.,6.};
   float c=0.;
   Division(6,v,c);
   for(int i=0;i<6;i++)   Message("\n%e",v[i]);
   }

}

//   ================================================================
//   =====================   SWAP   =================================
//   ================================================================
void Ex_Swap(void)
{
   Message("\n\n\n*** Examples of Swap ****\n");
   {
   Message("\n\nFirst example:\n");
   int i=1,j=8;
   Message("\nbefore Swap i %d j %d",i,j);
   Swap(&i,&j);
   Message("\nafter Swap i %d j %d",i,j);
   float x=1.,y=8.;
   Message("\nbefore Swap x %f y %f",x,y);
   Swap(&x,&y);
   Message("\nafter Swap x %f y %f",x,y);
   }
   {
   Message("\n\nSecond example:\n");
   float w[]={1.,2.,3.};
   float v[]={4.,5.,6.,7.,8.,9.};
   float *x=w,*y=v;
   int i;
   for(i=0;i<3;i++)Message("\n x %f",x[i]);
   for(i=0;i<6;i++)Message("\n y %f",y[i]);
   Swap(&x,&y);
   for(i=0;i<6;i++)Message("\n x %f",x[i]);
   for(i=0;i<3;i++)Message("\n y %f",y[i]);
   }
}

//   ================================================================
//   ===================   TEMP_FILE   ==============================
//   ================================================================

   //    ******************* WARNING ***************************
   //    ***** YOU MUST HAVE DEFINED THE DIRECTORY *************
   //    *********************** C:\TEMP\ **********************

void Ex_TempFile(void)
   {
   Message("\n\n\n*** Examples using TempFile class ***\n");
   const int SIZE = 50;
   TempFile f1("C:\\TEMP\\");
   TempFile f2("C:\\TEMP\\");
   TempFile f3("C:\\TEMP\\");
   TempFile f4("C:\\TEMP\\");
   TempFile ff[10];

   Message("\nFile %s",f1.FileName());
   Message("\nFile %s",f2.FileName());
   Message("\nFile %s",f3.FileName());
   Message("\nFile %s",f4.FileName());
   for(int k = 0; k < 10; k++)
      {
      ff[k].NewFileName("C:\\TEMP\\");
      Message("\nFile %s",ff[k].FileName());
      }

   FILE *buInOut;
   float vet[SIZE];
   float *ww = new float [SIZE];
   long offset;
   int i;
   float pro;

   Message("\nWARNING: Uses the directory C:\\TEMP\n");
   if((buInOut=fopen(ff[4].FileName(),"wb+"))==NULL)
       Error("%s%s",
       ERR_OPEN_FILE,ff[4].FileName());

   for(i = 0;i < SIZE;i++) vet[i] = (float)i;

   if(fwrite(vet,sizeof(vet),1,buInOut) != 1)
      Error("Couldn't write %d float",SIZE);

   // search an element
   offset=(long)10*sizeof(float);
   if(fseek(buInOut,offset,0) !=0)
      Error("error in fseek");

   if(fread(&pro,sizeof(float),1,buInOut) != 1)
      Error("when reading pro");
   Message("\npro %f",pro);

   // remember rewind !!!!
   rewind(buInOut);

   offset=(long)SIZE*sizeof(float);
   if(fread(ww,offset,1,buInOut) != 1)
      Error("Not reading %d float",SIZE);
   Message("\nmust be equal to 49: %f", ww[49]);
   fclose(buInOut);
   delete ww;
   }

//   ================================================================
//   ====================   ERROR   =================================
//   ================================================================
void Ex_Error(void)
   {
   Message("\n\n\n*** Example of Error ***\n");
   int iter,itmax=1000;
   iter = 1001;
   if(iter > itmax)Error("\nThe variable iter is worth %d",iter);
   } // end Error