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Integer Multiplication

As another example, consider the multiplication of two single-precision, FP numbers.

In general, the multiplication of two 24-bit binary numbers () gives a 48-bit result. This can be easily achieved if we do the multiplication in double precision (where the mantissa has 53 available bits), then round the result back to single precision.

However, if the two numbers to be multiplied are double-precision, the exact result needs a 106-bit long mantissa; this is more than even extended precision can provide. Usually, multiplications and divisions are performed by specialized hardware, able to handle this kind of problems.

Adrian Sandu 2001-08-26