C / C++ / MFC

BOOL IsEqualish (double d1, double d2, double dEpsilon)
{
    ASSERT(dEpsilon > 0.0);
    d1 -= d2;
    if (d1 < 0.0)
        d1 = -d1;    // or just d1 = abs (d1);
    return (d1 <= dEpsilon)
}

BOOL IsEqualish (double d1, double d2, double dEpsilon) { return abs (d1 - d2) <= dEpsilon; }

mohit`12 wrote:

I didn't get your code why would i use epsilon ?

mohit`12 wrote:

and it has to be FLOAT

fabs

viaducting wrote:

I think you want fabs

bool near_enough_equals( double a, double b )
{
    return (b - a) < ( (b + a) / 2000.0 );
}

bool are_these_two_near_enough( double a, double b )
{
    a = std::fabs( a ); b = fabs( b );

    return std::fabs( a - b ) < ( ( a + b ) / 2000.0 );
}

template< typename T >
bool are_these_two_floating_point_values_near_enough( T a, T b )

mohit`12 wrote:

if(value1==value2)
return true;
else
return false;

double a = 1.00003;
double b = 0.99997;
a *= 100;
b *= 100;
a += 0.5;
b += 0.5;

if (::floor(a) == ::floor(b))
{
    // Wooha!
}

a = 0.09999;
a *= 100; // a = 9.999
a += 0.5; // a = 10.499
floor(a); // a = 10.0

b = 0.10001;
b *= 100; // b = 10.001
b += 0.5; // b = 10.051
floor(b); // b = 10.0

printf("ceil of 2.3 is %.1lf\n", ceil (2.3));

ceil of 2.3 is 3.0

float a = 1.555;
float b = floor(a); // b = 1
float c = ceil(a);  // c = 2

a = 0.09999;
b = floor(a); // b = 0
c = ceil(a);  // c = 1

fasked wrote:

Why add 0.5?

float is=0.999999877543;
float closeTo=1.0;
bool closeEnough=abs(is-closeTo)<0.01;

float is=12.999999877543;
float closeTo=13.0;
bool closeEnough=abs((is-closeTo)/closeTo)<1.0e-6;

float previous=...;
float current=...;
float threshold=0.1e-3;  // an absolute tolerance of 0.1 millivolt for small voltages
if (abs(previous)>1) threshold+=abs(previous)*100.0e-6;  // a relative tolerance of 100 ppm
bool converged = abs(current-previous) < threshold;

float error = 0.00000013;
float lowv = 0.1 - error;
float highv = 0.1 + error;

if ((lowv <= myfloat) && (highv >= myfloat)) {
// good value 
} else {
// bad value
}

Chesnokov Yuriy wrote:

Those are neither present ...