1 - 111 1111 1011 - 0011 1110 1100 1100 0111 0010 0111 0110 0010 0010 0011 0100 0001 64 Bit Double Precision IEEE 754 Binary Floating Point Representation Standard Converted to Decimal
1 - 111 1111 1011 - 0011 1110 1100 1100 0111 0010 0111 0110 0010 0010 0011 0100 0001: 64 bit double precision IEEE 754 binary floating point representation standard converted to decimal
What are the steps to convert
1 - 111 1111 1011 - 0011 1110 1100 1100 0111 0010 0111 0110 0010 0010 0011 0100 0001, 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 1011
The last 52 bits contain the mantissa:
0011 1110 1100 1100 0111 0010 0111 0110 0010 0010 0011 0100 0001
2. Convert the exponent from binary (from base 2) to decimal (in base 10).
The exponent is allways a positive integer.
111 1111 1011(2) =
1 × 210 + 1 × 29 + 1 × 28 + 1 × 27 + 1 × 26 + 1 × 25 + 1 × 24 + 1 × 23 + 0 × 22 + 1 × 21 + 1 × 20 =
1,024 + 512 + 256 + 128 + 64 + 32 + 16 + 8 + 0 + 2 + 1 =
1,024 + 512 + 256 + 128 + 64 + 32 + 16 + 8 + 2 + 1 =
2,043(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 = 2,043 - 1023 = 1020
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).
0011 1110 1100 1100 0111 0010 0111 0110 0010 0010 0011 0100 0001(2) =
0 × 2-1 + 0 × 2-2 + 1 × 2-3 + 1 × 2-4 + 1 × 2-5 + 1 × 2-6 + 1 × 2-7 + 0 × 2-8 + 1 × 2-9 + 1 × 2-10 + 0 × 2-11 + 0 × 2-12 + 1 × 2-13 + 1 × 2-14 + 0 × 2-15 + 0 × 2-16 + 0 × 2-17 + 1 × 2-18 + 1 × 2-19 + 1 × 2-20 + 0 × 2-21 + 0 × 2-22 + 1 × 2-23 + 0 × 2-24 + 0 × 2-25 + 1 × 2-26 + 1 × 2-27 + 1 × 2-28 + 0 × 2-29 + 1 × 2-30 + 1 × 2-31 + 0 × 2-32 + 0 × 2-33 + 0 × 2-34 + 1 × 2-35 + 0 × 2-36 + 0 × 2-37 + 0 × 2-38 + 1 × 2-39 + 0 × 2-40 + 0 × 2-41 + 0 × 2-42 + 1 × 2-43 + 1 × 2-44 + 0 × 2-45 + 1 × 2-46 + 0 × 2-47 + 0 × 2-48 + 0 × 2-49 + 0 × 2-50 + 0 × 2-51 + 1 × 2-52 =
0 + 0 + 0.125 + 0.062 5 + 0.031 25 + 0.015 625 + 0.007 812 5 + 0 + 0.001 953 125 + 0.000 976 562 5 + 0 + 0 + 0.000 122 070 312 5 + 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 + 0 + 0.000 000 119 209 289 550 781 25 + 0 + 0 + 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 + 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 + 0 + 0 + 0.000 000 000 001 818 989 403 545 856 475 830 078 125 + 0 + 0 + 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 + 0.000 000 000 000 014 210 854 715 202 003 717 422 485 351 562 5 + 0 + 0 + 0 + 0 + 0 + 0.000 000 000 000 000 222 044 604 925 031 308 084 726 333 618 164 062 5 =
0.125 + 0.062 5 + 0.031 25 + 0.015 625 + 0.007 812 5 + 0.001 953 125 + 0.000 976 562 5 + 0.000 122 070 312 5 + 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 + 0.000 000 119 209 289 550 781 25 + 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 + 0.000 000 000 931 322 574 615 478 515 625 + 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 + 0.000 000 000 001 818 989 403 545 856 475 830 078 125 + 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 + 0.000 000 000 000 014 210 854 715 202 003 717 422 485 351 562 5 + 0.000 000 000 000 000 222 044 604 925 031 308 084 726 333 618 164 062 5 =
0.245 307 115 403 378 128 704 048 322 106 245 905 160 903 930 664 062 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 + 0.245 307 115 403 378 128 704 048 322 106 245 905 160 903 930 664 062 5) × 21020 =
-1.245 307 115 403 378 128 704 048 322 106 245 905 160 903 930 664 062 5 × 21020 = ...
= -13 991 750 325 974 041 487 486 641 324 763 772 334 201 999 431 976 401 568 822 583 545 703 807 885 959 055 904 781 722 914 562 778 282 805 780 855 828 518 941 081 831 076 969 979 857 857 011 379 318 874 317 421 856 712 922 521 257 249 767 760 403 536 922 645 874 515 717 700 293 052 028 312 373 593 937 850 704 101 802 601 205 922 922 402 736 862 756 567 461 022 341 714 377 067 071 379 888 641 494 520 692 736
1 - 111 1111 1011 - 0011 1110 1100 1100 0111 0010 0111 0110 0010 0010 0011 0100 0001, a 64 bit double precision IEEE 754 binary floating point representation standard to a decimal number, written in base ten (double) = -13 991 750 325 974 041 487 486 641 324 763 772 334 201 999 431 976 401 568 822 583 545 703 807 885 959 055 904 781 722 914 562 778 282 805 780 855 828 518 941 081 831 076 969 979 857 857 011 379 318 874 317 421 856 712 922 521 257 249 767 760 403 536 922 645 874 515 717 700 293 052 028 312 373 593 937 850 704 101 802 601 205 922 922 402 736 862 756 567 461 022 341 714 377 067 071 379 888 641 494 520 692 736(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.