0 - 111 1110 0110 - 1001 1111 1100 1000 0000 0000 0000 0000 0000 0000 0000 0100 0110 64 Bit Double Precision IEEE 754 Binary Floating Point Representation Standard Converted to Decimal
0 - 111 1110 0110 - 1001 1111 1100 1000 0000 0000 0000 0000 0000 0000 0000 0100 0110: 64 bit double precision IEEE 754 binary floating point representation standard converted to decimal
What are the steps to convert
0 - 111 1110 0110 - 1001 1111 1100 1000 0000 0000 0000 0000 0000 0000 0000 0100 0110, 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 1110 0110
The last 52 bits contain the mantissa:
1001 1111 1100 1000 0000 0000 0000 0000 0000 0000 0000 0100 0110
2. Convert the exponent from binary (from base 2) to decimal (in base 10).
The exponent is allways a positive integer.
111 1110 0110(2) =
1 × 210 + 1 × 29 + 1 × 28 + 1 × 27 + 1 × 26 + 1 × 25 + 0 × 24 + 0 × 23 + 1 × 22 + 1 × 21 + 0 × 20 =
1,024 + 512 + 256 + 128 + 64 + 32 + 0 + 0 + 4 + 2 + 0 =
1,024 + 512 + 256 + 128 + 64 + 32 + 4 + 2 =
2,022(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 = 2,022 - 1023 = 999
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).
1001 1111 1100 1000 0000 0000 0000 0000 0000 0000 0000 0100 0110(2) =
1 × 2-1 + 0 × 2-2 + 0 × 2-3 + 1 × 2-4 + 1 × 2-5 + 1 × 2-6 + 1 × 2-7 + 1 × 2-8 + 1 × 2-9 + 1 × 2-10 + 0 × 2-11 + 0 × 2-12 + 1 × 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 + 1 × 2-46 + 0 × 2-47 + 0 × 2-48 + 0 × 2-49 + 1 × 2-50 + 1 × 2-51 + 0 × 2-52 =
0.5 + 0 + 0 + 0.062 5 + 0.031 25 + 0.015 625 + 0.007 812 5 + 0.003 906 25 + 0.001 953 125 + 0.000 976 562 5 + 0 + 0 + 0.000 122 070 312 5 + 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 + 0.000 000 000 000 014 210 854 715 202 003 717 422 485 351 562 5 + 0 + 0 + 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 =
0.5 + 0.062 5 + 0.031 25 + 0.015 625 + 0.007 812 5 + 0.003 906 25 + 0.001 953 125 + 0.000 976 562 5 + 0.000 122 070 312 5 + 0.000 000 000 000 014 210 854 715 202 003 717 422 485 351 562 5 + 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 =
0.624 145 507 812 515 543 122 344 752 191 565 930 843 353 271 484 375(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 + 0.624 145 507 812 515 543 122 344 752 191 565 930 843 353 271 484 375) × 2999 =
1.624 145 507 812 515 543 122 344 752 191 565 930 843 353 271 484 375 × 2999 = ...
= 8 701 429 454 720 106 896 737 643 357 989 776 023 482 007 612 535 691 475 961 367 948 835 996 634 465 134 332 918 502 905 339 518 988 646 587 812 079 879 011 705 286 992 033 380 619 371 615 962 711 458 194 499 790 704 834 931 343 239 740 319 307 042 177 121 169 308 410 709 048 629 248 025 196 480 455 500 388 086 371 916 811 995 029 863 033 129 321 608 851 571 927 094 054 855 891 288 551 042 580 480
0 - 111 1110 0110 - 1001 1111 1100 1000 0000 0000 0000 0000 0000 0000 0000 0100 0110, a 64 bit double precision IEEE 754 binary floating point representation standard to a decimal number, written in base ten (double) = 8 701 429 454 720 106 896 737 643 357 989 776 023 482 007 612 535 691 475 961 367 948 835 996 634 465 134 332 918 502 905 339 518 988 646 587 812 079 879 011 705 286 992 033 380 619 371 615 962 711 458 194 499 790 704 834 931 343 239 740 319 307 042 177 121 169 308 410 709 048 629 248 025 196 480 455 500 388 086 371 916 811 995 029 863 033 129 321 608 851 571 927 094 054 855 891 288 551 042 580 480(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.