Double precision

[tech_man]

Is there a way to check and see if log(a)/log(5) equals a integer? Eg. log(125)/log(5) = 3 good! log(130)/log(5) = 3.024 bad!

[Franklin52]

Something like (assuming you are using C/C++):

if( int(log(a)/log(b)) - log(a)/log(b) == 0 ) then {
	// log(a)/log(b) equals an integer
}

Regards

[tech_man]

I'm using C++, but:

if( int(log(125)/log(5)) - (log(125)/log(5)) == 0 )
cout << "Yes";

is still a no go. It will not print yes.

[tech_man]

Got it. I had to use a radius of equality.

bool almost_zero(double a)
{
float b = (a * 1000);
int c = int(b);
b = float(c) / 1000;
if(((int)a - b == 0))
return true;
else
return false;
}