1 - 111 1111 1000 - 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0010 0100 0011 64 Bit Double Precision IEEE 754 Binary Floating Point Representation Standard Converted to Decimal
1 - 111 1111 1000 - 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0010 0100 0011: 64 bit double precision IEEE 754 binary floating point representation standard converted to decimal
What are the steps to convert
1 - 111 1111 1000 - 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0010 0100 0011, 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:
111 1111 1000
The last 52 bits contain the mantissa:
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0010 0100 0011
2. Convert the exponent from binary (from base 2) to decimal (in base 10).
The exponent is allways a positive integer.
111 1111 1000(2) =
1 × 210 + 1 × 29 + 1 × 28 + 1 × 27 + 1 × 26 + 1 × 25 + 1 × 24 + 1 × 23 + 0 × 22 + 0 × 21 + 0 × 20 =
1,024 + 512 + 256 + 128 + 64 + 32 + 16 + 8 + 0 + 0 + 0 =
1,024 + 512 + 256 + 128 + 64 + 32 + 16 + 8 =
2,040(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 = 2,040 - 1023 = 1017
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 0000 0000 0000 0000 0000 0000 0000 0000 0000 0010 0100 0011(2) =
0 × 2-1 + 0 × 2-2 + 0 × 2-3 + 0 × 2-4 + 0 × 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 + 1 × 2-43 + 0 × 2-44 + 0 × 2-45 + 1 × 2-46 + 0 × 2-47 + 0 × 2-48 + 0 × 2-49 + 0 × 2-50 + 1 × 2-51 + 1 × 2-52 =
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 + 0.000 000 000 000 113 686 837 721 616 029 739 379 882 812 5 + 0 + 0 + 0.000 000 000 000 014 210 854 715 202 003 717 422 485 351 562 5 + 0 + 0 + 0 + 0 + 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 =
0.000 000 000 000 113 686 837 721 616 029 739 379 882 812 5 + 0.000 000 000 000 014 210 854 715 202 003 717 422 485 351 562 5 + 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 =
0.000 000 000 000 128 563 826 251 593 127 381 056 547 164 916 992 187 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 + 0.000 000 000 000 128 563 826 251 593 127 381 056 547 164 916 992 187 5) × 21017 =
-1.000 000 000 000 128 563 826 251 593 127 381 056 547 164 916 992 187 5 × 21017 = ...
= -1 404 447 761 611 364 864 091 522 899 486 886 360 607 927 066 287 700 924 679 890 029 344 244 338 301 315 515 987 627 499 424 135 358 080 941 551 572 578 187 056 197 230 608 666 732 994 724 633 034 797 386 593 649 937 748 224 318 679 234 335 884 167 032 556 298 964 130 277 160 788 239 916 035 163 924 262 908 273 307 892 343 207 578 963 743 273 718 204 927 344 131 774 948 765 115 751 641 591 509 837 414 400
1 - 111 1111 1000 - 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0010 0100 0011, a 64 bit double precision IEEE 754 binary floating point representation standard to a decimal number, written in base ten (double) = -1 404 447 761 611 364 864 091 522 899 486 886 360 607 927 066 287 700 924 679 890 029 344 244 338 301 315 515 987 627 499 424 135 358 080 941 551 572 578 187 056 197 230 608 666 732 994 724 633 034 797 386 593 649 937 748 224 318 679 234 335 884 167 032 556 298 964 130 277 160 788 239 916 035 163 924 262 908 273 307 892 343 207 578 963 743 273 718 204 927 344 131 774 948 765 115 751 641 591 509 837 414 400(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.