1 - 101 1111 0000 - 1100 1000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0001 64 Bit Double Precision IEEE 754 Binary Floating Point Representation Standard Converted to Decimal
1 - 101 1111 0000 - 1100 1000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0001: 64 bit double precision IEEE 754 binary floating point representation standard converted to decimal
What are the steps to convert
1 - 101 1111 0000 - 1100 1000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0001, a 64 bit double precision IEEE 754 binary floating point representation standard to decimal?
1. Identify the elements that make up the binary representation of the number:
The first bit (the leftmost) indicates the sign,
1 = negative, 0 = positive.
1
The next 11 bits contain the exponent:
101 1111 0000
The last 52 bits contain the mantissa:
1100 1000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0001
2. Convert the exponent from binary (from base 2) to decimal (in base 10).
The exponent is allways a positive integer.
101 1111 0000(2) =
1 × 210 + 0 × 29 + 1 × 28 + 1 × 27 + 1 × 26 + 1 × 25 + 1 × 24 + 0 × 23 + 0 × 22 + 0 × 21 + 0 × 20 =
1,024 + 0 + 256 + 128 + 64 + 32 + 16 + 0 + 0 + 0 + 0 =
1,024 + 256 + 128 + 64 + 32 + 16 =
1,520(10)
3. Adjust the exponent.
Subtract the excess bits: 2(11 - 1) - 1 = 1023,
that is due to the 11 bit excess/bias notation.
The exponent, adjusted = 1,520 - 1023 = 497
4. Convert the mantissa from binary (from base 2) to decimal (in base 10).
The mantissa represents the fractional part of the number (what comes after the whole part of the number, separated from it by a comma).
1100 1000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0001(2) =
1 × 2-1 + 1 × 2-2 + 0 × 2-3 + 0 × 2-4 + 1 × 2-5 + 0 × 2-6 + 0 × 2-7 + 0 × 2-8 + 0 × 2-9 + 0 × 2-10 + 0 × 2-11 + 0 × 2-12 + 0 × 2-13 + 0 × 2-14 + 0 × 2-15 + 0 × 2-16 + 0 × 2-17 + 0 × 2-18 + 0 × 2-19 + 0 × 2-20 + 0 × 2-21 + 0 × 2-22 + 0 × 2-23 + 0 × 2-24 + 0 × 2-25 + 0 × 2-26 + 0 × 2-27 + 0 × 2-28 + 0 × 2-29 + 0 × 2-30 + 0 × 2-31 + 0 × 2-32 + 0 × 2-33 + 0 × 2-34 + 0 × 2-35 + 0 × 2-36 + 0 × 2-37 + 0 × 2-38 + 0 × 2-39 + 0 × 2-40 + 0 × 2-41 + 0 × 2-42 + 0 × 2-43 + 0 × 2-44 + 0 × 2-45 + 0 × 2-46 + 0 × 2-47 + 0 × 2-48 + 0 × 2-49 + 0 × 2-50 + 0 × 2-51 + 1 × 2-52 =
0.5 + 0.25 + 0 + 0 + 0.031 25 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0.000 000 000 000 000 222 044 604 925 031 308 084 726 333 618 164 062 5 =
0.5 + 0.25 + 0.031 25 + 0.000 000 000 000 000 222 044 604 925 031 308 084 726 333 618 164 062 5 =
0.781 250 000 000 000 222 044 604 925 031 308 084 726 333 618 164 062 5(10)
5. Put all the numbers into expression to calculate the double precision floating point decimal value:
(-1)Sign × (1 + Mantissa) × 2(Adjusted exponent) =
(-1)1 × (1 + 0.781 250 000 000 000 222 044 604 925 031 308 084 726 333 618 164 062 5) × 2497 =
-1.781 250 000 000 000 222 044 604 925 031 308 084 726 333 618 164 062 5 × 2497 = ...
= -728 840 877 539 375 429 099 964 805 385 131 442 401 212 691 564 842 938 738 559 179 592 412 325 792 003 216 440 639 120 669 180 013 264 508 452 483 222 742 155 961 230 561 067 036 238 855 383 547 904
1 - 101 1111 0000 - 1100 1000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0001, a 64 bit double precision IEEE 754 binary floating point representation standard to a decimal number, written in base ten (double) = -728 840 877 539 375 429 099 964 805 385 131 442 401 212 691 564 842 938 738 559 179 592 412 325 792 003 216 440 639 120 669 180 013 264 508 452 483 222 742 155 961 230 561 067 036 238 855 383 547 904(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.