Can we trust computers calculations?

Introduction

IEEE 754 specification is the standard used for floating-point calculations in the engineering and scientific fields. In my humble opinion it is a perfect example of how computer industry and software development are based on a fundamental illusion of mankind: the possibility to attain and manipulate infinity (infinitely small, infinitely big, it doesn't matter).

java.math.BigDecimal class represents “Immutable, arbitrary-precision signed decimal numbers” (with some limits), and has methods to operate on those numbers. Its use although is not so immediate and it is easy to do errors.

In this article I'll try to put some light on this topic, in the hope of seeing a lowering in the amount of bugs related to code using BigInteger and BigDecimal.

È possibile dubitare dei calcoli di un computer ?