The
approximation error in some data is the discrepancy between an exact value and some approximation to it. An approximation error can occur because
- the measurement of the data is not precise due to the instruments. (e.g., the accurate reading of a piece of paper is 4.5 cm but since the ruler does not use decimals, you round it to 5 cm.) or
- approximations are used instead of the real data (e.g., 3.14 instead of p).