Overview of IEEE Standard Single- and Double-Precision Formats
3-13
Instruction Set
SPRU733
Normalized:
−
1
s
×
2
(e
−
1023)
×
1.f 0 < e < 2047
Denormalized (Subnormal):
−
1
s
×
2
−
1022
×
0.f e = 0; f nonzero
Table 3
−
6 shows the s, e, and f values for special double-precision floating-
point numbers.
Table 3
−
6. Special Double-Precision Values
Symbol
Sign (s)
Exponent (e)
Fraction (f)
+0
0
0
0
−
0
1
0
0
+Inf
0
2047
0
−
Inf
1
2047
0
NaN
x
2047
nonzero
QNaN
x
2047
1xx..x
SNaN
x
2047
0xx..x and nonzero
Table 3
−
7 shows hexadecimal and decimal values for some double-precision
floating-point numbers.
Table 3
−
7. Hexadecimal and Decimal Representation for Selected Double-Precision Values
Symbol
Hex Value
Decimal Value
NaN_out
7FFF FFFF FFFF FFFF
QNaN
0
0000 0000 0000 0000
0.0
−
0
8000 0000 0000 0000
−
0.0
1
3FF0 0000 0000 0000
1.0
2
4000 0000 0000 0000
2.0
LFPN
7FEF FFFF FFFF FFFF
1.7976931348308
SFPN
0010 0000 0000 0000
2.2250738585072014e
−
308
LDFPN
000F FFFF FFFF FFFF
2.2250738585072009e
−
308
SDFPN
0000 0000 0000 0001
4.9406564584124654e
−
324