Unformatted text preview: rs.2 (There
is also a decimal version of the standard but we shall not discuss this.)
The IEEE standard has three very important requirements:
ANSI/IEEE Std 7541985. Thanks to Jim Demmel for introducing the author to the
standard.
2 4 consistent representation of oating point numbers across all machines
adopting the standard
correctly rounded arithmetic (to be explained in the next section)
consistent and sensible treatment of exceptional situations such as division by zero (to be discussed in the following section).
We will not describe the standard in detail, but we will cover the main
points.
We start with the following observation. In the last section, we chose to
normalize a nonzero number x so that x = m 2E , where 1 m < 2, i.e. m = (b0:b1b2b3 : : :)2
with b0 = 1. In the simple oating point model discussed in the previous
section, we stored the leading nonzero bit b0 in the rst position of the eld
provided for m. Note, however, that since we know this bit has the value one,
it is not necessary to store...
View
Full Document
 Spring '09
 LIE
 oating point

Click to edit the document details