0 - 111 1011 0001 - 0100 1010 1110 0100 0111 1110 0001 0101 1010 0101 0001 0000 0100 64 Bit Double Precision IEEE 754 Binary Floating Point Representation Standard Converted to Decimal
0 - 111 1011 0001 - 0100 1010 1110 0100 0111 1110 0001 0101 1010 0101 0001 0000 0100: 64 bit double precision IEEE 754 binary floating point representation standard converted to decimal
What are the steps to convert
0 - 111 1011 0001 - 0100 1010 1110 0100 0111 1110 0001 0101 1010 0101 0001 0000 0100, 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 1011 0001
The last 52 bits contain the mantissa:
0100 1010 1110 0100 0111 1110 0001 0101 1010 0101 0001 0000 0100
2. Convert the exponent from binary (from base 2) to decimal (in base 10).
The exponent is allways a positive integer.
111 1011 0001(2) =
1 × 210 + 1 × 29 + 1 × 28 + 1 × 27 + 0 × 26 + 1 × 25 + 1 × 24 + 0 × 23 + 0 × 22 + 0 × 21 + 1 × 20 =
1,024 + 512 + 256 + 128 + 0 + 32 + 16 + 0 + 0 + 0 + 1 =
1,024 + 512 + 256 + 128 + 32 + 16 + 1 =
1,969(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 = 1,969 - 1023 = 946
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).
0100 1010 1110 0100 0111 1110 0001 0101 1010 0101 0001 0000 0100(2) =
0 × 2-1 + 1 × 2-2 + 0 × 2-3 + 0 × 2-4 + 1 × 2-5 + 0 × 2-6 + 1 × 2-7 + 0 × 2-8 + 1 × 2-9 + 1 × 2-10 + 1 × 2-11 + 0 × 2-12 + 0 × 2-13 + 1 × 2-14 + 0 × 2-15 + 0 × 2-16 + 0 × 2-17 + 1 × 2-18 + 1 × 2-19 + 1 × 2-20 + 1 × 2-21 + 1 × 2-22 + 1 × 2-23 + 0 × 2-24 + 0 × 2-25 + 0 × 2-26 + 0 × 2-27 + 1 × 2-28 + 0 × 2-29 + 1 × 2-30 + 0 × 2-31 + 1 × 2-32 + 1 × 2-33 + 0 × 2-34 + 1 × 2-35 + 0 × 2-36 + 0 × 2-37 + 1 × 2-38 + 0 × 2-39 + 1 × 2-40 + 0 × 2-41 + 0 × 2-42 + 0 × 2-43 + 1 × 2-44 + 0 × 2-45 + 0 × 2-46 + 0 × 2-47 + 0 × 2-48 + 0 × 2-49 + 1 × 2-50 + 0 × 2-51 + 0 × 2-52 =
0 + 0.25 + 0 + 0 + 0.031 25 + 0 + 0.007 812 5 + 0 + 0.001 953 125 + 0.000 976 562 5 + 0.000 488 281 25 + 0 + 0 + 0.000 061 035 156 25 + 0 + 0 + 0 + 0.000 003 814 697 265 625 + 0.000 001 907 348 632 812 5 + 0.000 000 953 674 316 406 25 + 0.000 000 476 837 158 203 125 + 0.000 000 238 418 579 101 562 5 + 0.000 000 119 209 289 550 781 25 + 0 + 0 + 0 + 0 + 0.000 000 003 725 290 298 461 914 062 5 + 0 + 0.000 000 000 931 322 574 615 478 515 625 + 0 + 0.000 000 000 232 830 643 653 869 628 906 25 + 0.000 000 000 116 415 321 826 934 814 453 125 + 0 + 0.000 000 000 029 103 830 456 733 703 613 281 25 + 0 + 0 + 0.000 000 000 003 637 978 807 091 712 951 660 156 25 + 0 + 0.000 000 000 000 909 494 701 772 928 237 915 039 062 5 + 0 + 0 + 0 + 0.000 000 000 000 056 843 418 860 808 014 869 689 941 406 25 + 0 + 0 + 0 + 0 + 0 + 0.000 000 000 000 000 888 178 419 700 125 232 338 905 334 472 656 25 + 0 + 0 =
0.25 + 0.031 25 + 0.007 812 5 + 0.001 953 125 + 0.000 976 562 5 + 0.000 488 281 25 + 0.000 061 035 156 25 + 0.000 003 814 697 265 625 + 0.000 001 907 348 632 812 5 + 0.000 000 953 674 316 406 25 + 0.000 000 476 837 158 203 125 + 0.000 000 238 418 579 101 562 5 + 0.000 000 119 209 289 550 781 25 + 0.000 000 003 725 290 298 461 914 062 5 + 0.000 000 000 931 322 574 615 478 515 625 + 0.000 000 000 232 830 643 653 869 628 906 25 + 0.000 000 000 116 415 321 826 934 814 453 125 + 0.000 000 000 029 103 830 456 733 703 613 281 25 + 0.000 000 000 003 637 978 807 091 712 951 660 156 25 + 0.000 000 000 000 909 494 701 772 928 237 915 039 062 5 + 0.000 000 000 000 056 843 418 860 808 014 869 689 941 406 25 + 0.000 000 000 000 000 888 178 419 700 125 232 338 905 334 472 656 25 =
0.292 549 019 131 059 573 339 825 874 427 333 474 159 240 722 656 25(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 + 0.292 549 019 131 059 573 339 825 874 427 333 474 159 240 722 656 25) × 2946 =
1.292 549 019 131 059 573 339 825 874 427 333 474 159 240 722 656 25 × 2946 = ...
= 768 816 898 593 703 633 075 462 490 597 192 912 284 457 340 553 676 302 759 615 316 609 016 073 883 628 908 367 777 700 088 983 899 068 868 539 786 432 079 911 179 054 476 187 717 826 276 727 894 874 273 822 872 718 845 300 901 600 245 552 601 619 205 098 683 998 563 039 269 921 813 031 415 229 663 358 687 851 634 763 438 827 825 719 529 682 294 751 390 026 620 798 668 636 160
0 - 111 1011 0001 - 0100 1010 1110 0100 0111 1110 0001 0101 1010 0101 0001 0000 0100, a 64 bit double precision IEEE 754 binary floating point representation standard to a decimal number, written in base ten (double) = 768 816 898 593 703 633 075 462 490 597 192 912 284 457 340 553 676 302 759 615 316 609 016 073 883 628 908 367 777 700 088 983 899 068 868 539 786 432 079 911 179 054 476 187 717 826 276 727 894 874 273 822 872 718 845 300 901 600 245 552 601 619 205 098 683 998 563 039 269 921 813 031 415 229 663 358 687 851 634 763 438 827 825 719 529 682 294 751 390 026 620 798 668 636 160(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.