0 - 111 1111 1110 - 0000 0001 0000 0000 0000 0000 0000 0000 0000 0000 0000 0001 0111 64 Bit Double Precision IEEE 754 Binary Floating Point Representation Standard Converted to Decimal
0 - 111 1111 1110 - 0000 0001 0000 0000 0000 0000 0000 0000 0000 0000 0000 0001 0111: 64 bit double precision IEEE 754 binary floating point representation standard converted to decimal
What are the steps to convert
0 - 111 1111 1110 - 0000 0001 0000 0000 0000 0000 0000 0000 0000 0000 0000 0001 0111, 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.
0
The next 11 bits contain the exponent:
111 1111 1110
The last 52 bits contain the mantissa:
0000 0001 0000 0000 0000 0000 0000 0000 0000 0000 0000 0001 0111
2. Convert the exponent from binary (from base 2) to decimal (in base 10).
The exponent is allways a positive integer.
111 1111 1110(2) =
1 × 210 + 1 × 29 + 1 × 28 + 1 × 27 + 1 × 26 + 1 × 25 + 1 × 24 + 1 × 23 + 1 × 22 + 1 × 21 + 0 × 20 =
1,024 + 512 + 256 + 128 + 64 + 32 + 16 + 8 + 4 + 2 + 0 =
1,024 + 512 + 256 + 128 + 64 + 32 + 16 + 8 + 4 + 2 =
2,046(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 = 2,046 - 1023 = 1023
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).
0000 0001 0000 0000 0000 0000 0000 0000 0000 0000 0000 0001 0111(2) =
0 × 2-1 + 0 × 2-2 + 0 × 2-3 + 0 × 2-4 + 0 × 2-5 + 0 × 2-6 + 0 × 2-7 + 1 × 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 + 1 × 2-48 + 0 × 2-49 + 1 × 2-50 + 1 × 2-51 + 1 × 2-52 =
0 + 0 + 0 + 0 + 0 + 0 + 0 + 0.003 906 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 + 0.000 000 000 000 003 552 713 678 800 500 929 355 621 337 890 625 + 0 + 0.000 000 000 000 000 888 178 419 700 125 232 338 905 334 472 656 25 + 0.000 000 000 000 000 444 089 209 850 062 616 169 452 667 236 328 125 + 0.000 000 000 000 000 222 044 604 925 031 308 084 726 333 618 164 062 5 =
0.003 906 25 + 0.000 000 000 000 003 552 713 678 800 500 929 355 621 337 890 625 + 0.000 000 000 000 000 888 178 419 700 125 232 338 905 334 472 656 25 + 0.000 000 000 000 000 444 089 209 850 062 616 169 452 667 236 328 125 + 0.000 000 000 000 000 222 044 604 925 031 308 084 726 333 618 164 062 5 =
0.003 906 250 000 005 107 025 913 275 720 085 948 705 673 217 773 437 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)0 × (1 + 0.003 906 250 000 005 107 025 913 275 720 085 948 705 673 217 773 437 5) × 21023 =
1.003 906 250 000 005 107 025 913 275 720 085 948 705 673 217 773 437 5 × 21023 = ...
= 90 235 768 683 519 050 505 464 832 445 083 899 039 907 608 548 685 193 402 992 108 861 362 080 121 048 861 193 707 939 767 709 225 769 683 370 468 568 571 042 743 846 372 448 330 082 372 967 388 484 246 755 097 572 880 140 504 856 640 386 166 322 987 329 870 979 530 482 170 345 921 583 388 599 325 200 029 638 739 969 614 628 116 215 971 667 358 630 208 371 532 101 357 853 029 090 779 462 699 265 692 794 880
0 - 111 1111 1110 - 0000 0001 0000 0000 0000 0000 0000 0000 0000 0000 0000 0001 0111, a 64 bit double precision IEEE 754 binary floating point representation standard to a decimal number, written in base ten (double) = 90 235 768 683 519 050 505 464 832 445 083 899 039 907 608 548 685 193 402 992 108 861 362 080 121 048 861 193 707 939 767 709 225 769 683 370 468 568 571 042 743 846 372 448 330 082 372 967 388 484 246 755 097 572 880 140 504 856 640 386 166 322 987 329 870 979 530 482 170 345 921 583 388 599 325 200 029 638 739 969 614 628 116 215 971 667 358 630 208 371 532 101 357 853 029 090 779 462 699 265 692 794 880(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.