I tried but can not slove.Help.

Question

Create a Calculator class that will be able to add, subtract, multiply, divide, find the remainder, percentage.

You need to use header file and source file for the class and create objects and call the functions from the main.cpp file

Answer 1

using namespace std;

#include <iostream>

#include <math.h>

#include <string.h>

#include <cfloat>

#include <limits.h>

//calculator.h

#ifndef _CALCULATOR

#define _CALCULATOR

typedef struct _TStats

{

int N;

double minVal;

double maxVal;

double meanAvg;

double sumTotal;

double variance;

double median;

double skew;

} * TStats;

#define STATS_SIZE (sizeof(struct _TStats))

typedef

class Calculator

{

protected:

bool error_flag;

public:

Calculator()

{

error_flag=false;

}

bool GetError() { return(error_flag); }

void ClearError() { error_flag=false; }

double Add(double x , double y) { ClearError(); return(x+y); }

double Subtract( double x, double y) { ClearError(); return(x-y); }

double Multiply (double x, double y) { ClearError(); return(x*y); }

double Divide(double x, double y);

long Divide(long x, long y);

long Mod(long x,long y);

double PercentOf( double principal, double percent) { ClearError(); return(principal*percent/100); }

double PercentChange(double oldValue, double newValue);

double PercentIncrease(double principal,double percent) { ClearError(); return( principal*(1+percent/100)); }

double PercentDecrease(double principal,double percent){ ClearError(); return( principal*(1-percent/100)); }

double FutureValue(double principal, double percent, int n) { ClearError(); return( principal* pow((1+percent/100),n)); }

void Stats(double * a, TStats stats );

double zScore(double x, TStats stats) { ClearError(); return( (x-stats->meanAvg)/sqrt(stats->variance)); }

} * TCalculator;

#define CALCULATOR_SIZE (sizeof(Calculator))

#endif

double Calculator::Divide(double x, double y)

{

ClearError();

double retval;

if (y!=0)

{

retval = x/y;

}

else

{

retval = DBL_MAX;

error_flag=true;

}

return retval;

}

long Calculator::Divide(long x, long y)

{

ClearError();

long retval;

if (y!=0)

{

retval = x/y;

}

else

{

retval = LONG_MAX;

error_flag=true;

}

return retval;

}

long Calculator::Mod(long x,long y)

{

ClearError();

long retval;

if (y!=0)

{

retval = x%y;

}

else

{

retval = LONG_MAX;

error_flag=true;

}

return retval;

}

double Calculator::PercentChange(double oldValue, double newValue)

{

ClearError();

double retval;

if (newValue!=0)

{

retval = Divide((newValue-oldValue)*100,oldValue);

}

else

{

error_flag=true;

retval = DBL_MAX;;

}

return retval;

}

void Calculator::Stats(double * a, TStats stats )

{

ClearError();

if (stats->N>1)

{

double sumXSqr=0; // specifically, a[0]^2+ a[1]^2 + ... + a[N-1]^2

stats->sumTotal=0;

stats->maxVal = a[0];

stats->minVal = a[0];

for (int iLoop=0; iLoop<stats->N; iLoop++)

{

stats->sumTotal += a[iLoop];

sumXSqr += a[iLoop]*a[iLoop];

if (a[iLoop]>stats->maxVal) { stats->maxVal = a[iLoop]; }

if (a[iLoop]<stats->minVal) { stats->minVal = a[iLoop]; }

}

stats->meanAvg = stats->sumTotal/stats->N;

stats->variance = (sumXSqr - stats->N * stats->meanAvg*stats->meanAvg)/(stats->N-1);

int medianIndexPos = stats->N/2;

if ((stats->N%2)==0)

{

stats->median = (a[medianIndexPos]+a[medianIndexPos-1])/2;

}

else

{

stats->median = a[medianIndexPos];

}

stats->skew = (stats->meanAvg-stats->median)/stats->N;

}

else

{

memset(stats,0,STATS_SIZE);

error_flag=true; // division by zero on meanAvg if N=0 ;division by zero on variance if N=1

}

}

Go()

{

Calculator myCalculator;

double a[] = { 1.0, 2.5, 5,7.5};

struct _TStats stats;

stats.N=4;

myCalculator.Stats(a,&stats);

cout << stats.maxVal << endl;

cout << stats.minVal << endl;

cout << stats.meanAvg << endl;

cout << stats.median << endl;

cout << stats.variance << endl;

cout << stats.skew << endl;

cout << myCalculator.GetError() << endl;

// put your code here

}

int main()

{

Go();

}