Hi, I was wondering if boost provides any support for testing equality of two doubles. In principle in C/C++ you cannot rely on equality because it uses bitwise comparison of doubles and in arithmetic expressions results may have lost some precession. An example will help: #include <iostream> int main(void) { double start = 3.123; double end = 4.124; double diff = end - start; // == 1.001 ??? if (diff != 1.001) { std::cout << diff << " and " << 1.001 << " are not equal" << std::endl; } } On my machine, this example outputs: 1.001 and 1.001 are not equal I am using a lot of arithmetic expressions on floating-point values and also need to test for equality. Also, at compile-time I do not know the precession so comparing within the range of an epsilon seems impossible. So does boost have anything for this I don't know of? Or any other libraries? Thanks, Andrej ___________________________________________________________ Yahoo! Answers - Got a question? Someone out there knows the answer. Try it now. http://uk.answers.yahoo.com/