1 - 111 1101 1111 - 1011 0011 0010 0001 1100 1111 1001 0011 1111 0001 1000 1000 1011 64 Bit Double Precision IEEE 754 Binary Floating Point Representation Standard Converted to Decimal
1 - 111 1101 1111 - 1011 0011 0010 0001 1100 1111 1001 0011 1111 0001 1000 1000 1011: 64 bit double precision IEEE 754 binary floating point representation standard converted to decimal
What are the steps to convert
1 - 111 1101 1111 - 1011 0011 0010 0001 1100 1111 1001 0011 1111 0001 1000 1000 1011, 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 1101 1111
The last 52 bits contain the mantissa:
1011 0011 0010 0001 1100 1111 1001 0011 1111 0001 1000 1000 1011
2. Convert the exponent from binary (from base 2) to decimal (in base 10).
The exponent is allways a positive integer.
111 1101 1111(2) =
1 × 210 + 1 × 29 + 1 × 28 + 1 × 27 + 1 × 26 + 0 × 25 + 1 × 24 + 1 × 23 + 1 × 22 + 1 × 21 + 1 × 20 =
1,024 + 512 + 256 + 128 + 64 + 0 + 16 + 8 + 4 + 2 + 1 =
1,024 + 512 + 256 + 128 + 64 + 16 + 8 + 4 + 2 + 1 =
2,015(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 = 2,015 - 1023 = 992
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).
1011 0011 0010 0001 1100 1111 1001 0011 1111 0001 1000 1000 1011(2) =
1 × 2-1 + 0 × 2-2 + 1 × 2-3 + 1 × 2-4 + 0 × 2-5 + 0 × 2-6 + 1 × 2-7 + 1 × 2-8 + 0 × 2-9 + 0 × 2-10 + 1 × 2-11 + 0 × 2-12 + 0 × 2-13 + 0 × 2-14 + 0 × 2-15 + 1 × 2-16 + 1 × 2-17 + 1 × 2-18 + 0 × 2-19 + 0 × 2-20 + 1 × 2-21 + 1 × 2-22 + 1 × 2-23 + 1 × 2-24 + 1 × 2-25 + 0 × 2-26 + 0 × 2-27 + 1 × 2-28 + 0 × 2-29 + 0 × 2-30 + 1 × 2-31 + 1 × 2-32 + 1 × 2-33 + 1 × 2-34 + 1 × 2-35 + 1 × 2-36 + 0 × 2-37 + 0 × 2-38 + 0 × 2-39 + 1 × 2-40 + 1 × 2-41 + 0 × 2-42 + 0 × 2-43 + 0 × 2-44 + 1 × 2-45 + 0 × 2-46 + 0 × 2-47 + 0 × 2-48 + 1 × 2-49 + 0 × 2-50 + 1 × 2-51 + 1 × 2-52 =
0.5 + 0 + 0.125 + 0.062 5 + 0 + 0 + 0.007 812 5 + 0.003 906 25 + 0 + 0 + 0.000 488 281 25 + 0 + 0 + 0 + 0 + 0.000 015 258 789 062 5 + 0.000 007 629 394 531 25 + 0.000 003 814 697 265 625 + 0 + 0 + 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 + 0.000 000 059 604 644 775 390 625 + 0.000 000 029 802 322 387 695 312 5 + 0 + 0 + 0.000 000 003 725 290 298 461 914 062 5 + 0 + 0 + 0.000 000 000 465 661 287 307 739 257 812 5 + 0.000 000 000 232 830 643 653 869 628 906 25 + 0.000 000 000 116 415 321 826 934 814 453 125 + 0.000 000 000 058 207 660 913 467 407 226 562 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 + 0 + 0 + 0.000 000 000 000 909 494 701 772 928 237 915 039 062 5 + 0.000 000 000 000 454 747 350 886 464 118 957 519 531 25 + 0 + 0 + 0 + 0.000 000 000 000 028 421 709 430 404 007 434 844 970 703 125 + 0 + 0 + 0 + 0.000 000 000 000 001 776 356 839 400 250 464 677 810 668 945 312 5 + 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 =
0.5 + 0.125 + 0.062 5 + 0.007 812 5 + 0.003 906 25 + 0.000 488 281 25 + 0.000 015 258 789 062 5 + 0.000 007 629 394 531 25 + 0.000 003 814 697 265 625 + 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 + 0.000 000 059 604 644 775 390 625 + 0.000 000 029 802 322 387 695 312 5 + 0.000 000 003 725 290 298 461 914 062 5 + 0.000 000 000 465 661 287 307 739 257 812 5 + 0.000 000 000 232 830 643 653 869 628 906 25 + 0.000 000 000 116 415 321 826 934 814 453 125 + 0.000 000 000 058 207 660 913 467 407 226 562 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 + 0.000 000 000 000 909 494 701 772 928 237 915 039 062 5 + 0.000 000 000 000 454 747 350 886 464 118 957 519 531 25 + 0.000 000 000 000 028 421 709 430 404 007 434 844 970 703 125 + 0.000 000 000 000 001 776 356 839 400 250 464 677 810 668 945 312 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 =
0.699 734 662 646 309 457 656 457 198 027 055 710 554 122 924 804 687 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 + 0.699 734 662 646 309 457 656 457 198 027 055 710 554 122 924 804 687 5) × 2992 =
-1.699 734 662 646 309 457 656 457 198 027 055 710 554 122 924 804 687 5 × 2992 = ...
= -71 143 762 537 436 211 039 011 681 179 325 275 389 773 376 042 065 917 858 734 040 528 862 608 650 425 175 416 985 874 268 662 925 825 119 859 949 214 733 217 694 783 338 718 456 302 438 433 373 812 776 125 475 950 883 128 990 377 631 502 134 368 872 871 648 934 863 411 713 464 740 616 092 082 061 583 495 393 789 449 605 199 751 881 780 701 819 811 092 211 283 153 750 397 343 414 309 628 149 760
1 - 111 1101 1111 - 1011 0011 0010 0001 1100 1111 1001 0011 1111 0001 1000 1000 1011, a 64 bit double precision IEEE 754 binary floating point representation standard to a decimal number, written in base ten (double) = -71 143 762 537 436 211 039 011 681 179 325 275 389 773 376 042 065 917 858 734 040 528 862 608 650 425 175 416 985 874 268 662 925 825 119 859 949 214 733 217 694 783 338 718 456 302 438 433 373 812 776 125 475 950 883 128 990 377 631 502 134 368 872 871 648 934 863 411 713 464 740 616 092 082 061 583 495 393 789 449 605 199 751 881 780 701 819 811 092 211 283 153 750 397 343 414 309 628 149 760(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.