1 - 111 1111 1110 - 1001 0011 0001 0000 0010 0010 1111 1110 0011 0100 1011 1010 1101 64 Bit Double Precision IEEE 754 Binary Floating Point Representation Standard Converted to Decimal
1 - 111 1111 1110 - 1001 0011 0001 0000 0010 0010 1111 1110 0011 0100 1011 1010 1101: 64 bit double precision IEEE 754 binary floating point representation standard converted to decimal
What are the steps to convert
1 - 111 1111 1110 - 1001 0011 0001 0000 0010 0010 1111 1110 0011 0100 1011 1010 1101, 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 1110
The last 52 bits contain the mantissa:
1001 0011 0001 0000 0010 0010 1111 1110 0011 0100 1011 1010 1101
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).
1001 0011 0001 0000 0010 0010 1111 1110 0011 0100 1011 1010 1101(2) =
1 × 2-1 + 0 × 2-2 + 0 × 2-3 + 1 × 2-4 + 0 × 2-5 + 0 × 2-6 + 1 × 2-7 + 1 × 2-8 + 0 × 2-9 + 0 × 2-10 + 0 × 2-11 + 1 × 2-12 + 0 × 2-13 + 0 × 2-14 + 0 × 2-15 + 0 × 2-16 + 0 × 2-17 + 0 × 2-18 + 1 × 2-19 + 0 × 2-20 + 0 × 2-21 + 0 × 2-22 + 1 × 2-23 + 0 × 2-24 + 1 × 2-25 + 1 × 2-26 + 1 × 2-27 + 1 × 2-28 + 1 × 2-29 + 1 × 2-30 + 1 × 2-31 + 0 × 2-32 + 0 × 2-33 + 0 × 2-34 + 1 × 2-35 + 1 × 2-36 + 0 × 2-37 + 1 × 2-38 + 0 × 2-39 + 0 × 2-40 + 1 × 2-41 + 0 × 2-42 + 1 × 2-43 + 1 × 2-44 + 1 × 2-45 + 0 × 2-46 + 1 × 2-47 + 0 × 2-48 + 1 × 2-49 + 1 × 2-50 + 0 × 2-51 + 1 × 2-52 =
0.5 + 0 + 0 + 0.062 5 + 0 + 0 + 0.007 812 5 + 0.003 906 25 + 0 + 0 + 0 + 0.000 244 140 625 + 0 + 0 + 0 + 0 + 0 + 0 + 0.000 001 907 348 632 812 5 + 0 + 0 + 0 + 0.000 000 119 209 289 550 781 25 + 0 + 0.000 000 029 802 322 387 695 312 5 + 0.000 000 014 901 161 193 847 656 25 + 0.000 000 007 450 580 596 923 828 125 + 0.000 000 003 725 290 298 461 914 062 5 + 0.000 000 001 862 645 149 230 957 031 25 + 0.000 000 000 931 322 574 615 478 515 625 + 0.000 000 000 465 661 287 307 739 257 812 5 + 0 + 0 + 0 + 0.000 000 000 029 103 830 456 733 703 613 281 25 + 0.000 000 000 014 551 915 228 366 851 806 640 625 + 0 + 0.000 000 000 003 637 978 807 091 712 951 660 156 25 + 0 + 0 + 0.000 000 000 000 454 747 350 886 464 118 957 519 531 25 + 0 + 0.000 000 000 000 113 686 837 721 616 029 739 379 882 812 5 + 0.000 000 000 000 056 843 418 860 808 014 869 689 941 406 25 + 0.000 000 000 000 028 421 709 430 404 007 434 844 970 703 125 + 0 + 0.000 000 000 000 007 105 427 357 601 001 858 711 242 675 781 25 + 0 + 0.000 000 000 000 001 776 356 839 400 250 464 677 810 668 945 312 5 + 0.000 000 000 000 000 888 178 419 700 125 232 338 905 334 472 656 25 + 0 + 0.000 000 000 000 000 222 044 604 925 031 308 084 726 333 618 164 062 5 =
0.5 + 0.062 5 + 0.007 812 5 + 0.003 906 25 + 0.000 244 140 625 + 0.000 001 907 348 632 812 5 + 0.000 000 119 209 289 550 781 25 + 0.000 000 029 802 322 387 695 312 5 + 0.000 000 014 901 161 193 847 656 25 + 0.000 000 007 450 580 596 923 828 125 + 0.000 000 003 725 290 298 461 914 062 5 + 0.000 000 001 862 645 149 230 957 031 25 + 0.000 000 000 931 322 574 615 478 515 625 + 0.000 000 000 465 661 287 307 739 257 812 5 + 0.000 000 000 029 103 830 456 733 703 613 281 25 + 0.000 000 000 014 551 915 228 366 851 806 640 625 + 0.000 000 000 003 637 978 807 091 712 951 660 156 25 + 0.000 000 000 000 454 747 350 886 464 118 957 519 531 25 + 0.000 000 000 000 113 686 837 721 616 029 739 379 882 812 5 + 0.000 000 000 000 056 843 418 860 808 014 869 689 941 406 25 + 0.000 000 000 000 028 421 709 430 404 007 434 844 970 703 125 + 0.000 000 000 000 007 105 427 357 601 001 858 711 242 675 781 25 + 0.000 000 000 000 001 776 356 839 400 250 464 677 810 668 945 312 5 + 0.000 000 000 000 000 888 178 419 700 125 232 338 905 334 472 656 25 + 0.000 000 000 000 000 222 044 604 925 031 308 084 726 333 618 164 062 5 =
0.574 464 976 369 863 267 180 448 929 138 947 278 261 184 692 382 812 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 + 0.574 464 976 369 863 267 180 448 929 138 947 278 261 184 692 382 812 5) × 21023 =
-1.574 464 976 369 863 267 180 448 929 138 947 278 261 184 692 382 812 5 × 21023 = ...
= -141 520 243 955 063 081 760 773 913 481 874 532 701 593 654 260 675 752 998 544 204 962 475 149 485 277 946 890 503 998 648 988 755 761 785 995 159 344 115 365 650 271 313 967 797 182 035 882 959 442 309 182 764 401 931 260 503 327 106 091 661 679 244 589 161 275 302 728 988 228 977 470 765 467 809 506 166 405 322 454 969 752 693 258 054 883 418 981 923 458 972 050 715 301 364 718 237 664 331 819 724 570 624
1 - 111 1111 1110 - 1001 0011 0001 0000 0010 0010 1111 1110 0011 0100 1011 1010 1101, a 64 bit double precision IEEE 754 binary floating point representation standard to a decimal number, written in base ten (double) = -141 520 243 955 063 081 760 773 913 481 874 532 701 593 654 260 675 752 998 544 204 962 475 149 485 277 946 890 503 998 648 988 755 761 785 995 159 344 115 365 650 271 313 967 797 182 035 882 959 442 309 182 764 401 931 260 503 327 106 091 661 679 244 589 161 275 302 728 988 228 977 470 765 467 809 506 166 405 322 454 969 752 693 258 054 883 418 981 923 458 972 050 715 301 364 718 237 664 331 819 724 570 624(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.