0.000 020 830 729 321 671 205 134 999 154 509 660 617 445 Converted to 64 Bit Double Precision IEEE 754 Binary Floating Point Representation Standard

Convert decimal 0.000 020 830 729 321 671 205 134 999 154 509 660 617 445(10) to 64 bit double precision IEEE 754 binary floating point representation standard (1 bit for sign, 11 bits for exponent, 52 bits for mantissa)

What are the steps to convert decimal number
0.000 020 830 729 321 671 205 134 999 154 509 660 617 445(10) to 64 bit double precision IEEE 754 binary floating point representation (1 bit for sign, 11 bits for exponent, 52 bits for mantissa)

1. First, convert to binary (in base 2) the integer part: 0.
Divide the number repeatedly by 2.

Keep track of each remainder.

We stop when we get a quotient that is equal to zero.


  • division = quotient + remainder;
  • 0 ÷ 2 = 0 + 0;

2. Construct the base 2 representation of the integer part of the number.

Take all the remainders starting from the bottom of the list constructed above.

0(10) =


0(2)


3. Convert to binary (base 2) the fractional part: 0.000 020 830 729 321 671 205 134 999 154 509 660 617 445.

Multiply it repeatedly by 2.


Keep track of each integer part of the results.


Stop when we get a fractional part that is equal to zero.


  • #) multiplying = integer + fractional part;
  • 1) 0.000 020 830 729 321 671 205 134 999 154 509 660 617 445 × 2 = 0 + 0.000 041 661 458 643 342 410 269 998 309 019 321 234 89;
  • 2) 0.000 041 661 458 643 342 410 269 998 309 019 321 234 89 × 2 = 0 + 0.000 083 322 917 286 684 820 539 996 618 038 642 469 78;
  • 3) 0.000 083 322 917 286 684 820 539 996 618 038 642 469 78 × 2 = 0 + 0.000 166 645 834 573 369 641 079 993 236 077 284 939 56;
  • 4) 0.000 166 645 834 573 369 641 079 993 236 077 284 939 56 × 2 = 0 + 0.000 333 291 669 146 739 282 159 986 472 154 569 879 12;
  • 5) 0.000 333 291 669 146 739 282 159 986 472 154 569 879 12 × 2 = 0 + 0.000 666 583 338 293 478 564 319 972 944 309 139 758 24;
  • 6) 0.000 666 583 338 293 478 564 319 972 944 309 139 758 24 × 2 = 0 + 0.001 333 166 676 586 957 128 639 945 888 618 279 516 48;
  • 7) 0.001 333 166 676 586 957 128 639 945 888 618 279 516 48 × 2 = 0 + 0.002 666 333 353 173 914 257 279 891 777 236 559 032 96;
  • 8) 0.002 666 333 353 173 914 257 279 891 777 236 559 032 96 × 2 = 0 + 0.005 332 666 706 347 828 514 559 783 554 473 118 065 92;
  • 9) 0.005 332 666 706 347 828 514 559 783 554 473 118 065 92 × 2 = 0 + 0.010 665 333 412 695 657 029 119 567 108 946 236 131 84;
  • 10) 0.010 665 333 412 695 657 029 119 567 108 946 236 131 84 × 2 = 0 + 0.021 330 666 825 391 314 058 239 134 217 892 472 263 68;
  • 11) 0.021 330 666 825 391 314 058 239 134 217 892 472 263 68 × 2 = 0 + 0.042 661 333 650 782 628 116 478 268 435 784 944 527 36;
  • 12) 0.042 661 333 650 782 628 116 478 268 435 784 944 527 36 × 2 = 0 + 0.085 322 667 301 565 256 232 956 536 871 569 889 054 72;
  • 13) 0.085 322 667 301 565 256 232 956 536 871 569 889 054 72 × 2 = 0 + 0.170 645 334 603 130 512 465 913 073 743 139 778 109 44;
  • 14) 0.170 645 334 603 130 512 465 913 073 743 139 778 109 44 × 2 = 0 + 0.341 290 669 206 261 024 931 826 147 486 279 556 218 88;
  • 15) 0.341 290 669 206 261 024 931 826 147 486 279 556 218 88 × 2 = 0 + 0.682 581 338 412 522 049 863 652 294 972 559 112 437 76;
  • 16) 0.682 581 338 412 522 049 863 652 294 972 559 112 437 76 × 2 = 1 + 0.365 162 676 825 044 099 727 304 589 945 118 224 875 52;
  • 17) 0.365 162 676 825 044 099 727 304 589 945 118 224 875 52 × 2 = 0 + 0.730 325 353 650 088 199 454 609 179 890 236 449 751 04;
  • 18) 0.730 325 353 650 088 199 454 609 179 890 236 449 751 04 × 2 = 1 + 0.460 650 707 300 176 398 909 218 359 780 472 899 502 08;
  • 19) 0.460 650 707 300 176 398 909 218 359 780 472 899 502 08 × 2 = 0 + 0.921 301 414 600 352 797 818 436 719 560 945 799 004 16;
  • 20) 0.921 301 414 600 352 797 818 436 719 560 945 799 004 16 × 2 = 1 + 0.842 602 829 200 705 595 636 873 439 121 891 598 008 32;
  • 21) 0.842 602 829 200 705 595 636 873 439 121 891 598 008 32 × 2 = 1 + 0.685 205 658 401 411 191 273 746 878 243 783 196 016 64;
  • 22) 0.685 205 658 401 411 191 273 746 878 243 783 196 016 64 × 2 = 1 + 0.370 411 316 802 822 382 547 493 756 487 566 392 033 28;
  • 23) 0.370 411 316 802 822 382 547 493 756 487 566 392 033 28 × 2 = 0 + 0.740 822 633 605 644 765 094 987 512 975 132 784 066 56;
  • 24) 0.740 822 633 605 644 765 094 987 512 975 132 784 066 56 × 2 = 1 + 0.481 645 267 211 289 530 189 975 025 950 265 568 133 12;
  • 25) 0.481 645 267 211 289 530 189 975 025 950 265 568 133 12 × 2 = 0 + 0.963 290 534 422 579 060 379 950 051 900 531 136 266 24;
  • 26) 0.963 290 534 422 579 060 379 950 051 900 531 136 266 24 × 2 = 1 + 0.926 581 068 845 158 120 759 900 103 801 062 272 532 48;
  • 27) 0.926 581 068 845 158 120 759 900 103 801 062 272 532 48 × 2 = 1 + 0.853 162 137 690 316 241 519 800 207 602 124 545 064 96;
  • 28) 0.853 162 137 690 316 241 519 800 207 602 124 545 064 96 × 2 = 1 + 0.706 324 275 380 632 483 039 600 415 204 249 090 129 92;
  • 29) 0.706 324 275 380 632 483 039 600 415 204 249 090 129 92 × 2 = 1 + 0.412 648 550 761 264 966 079 200 830 408 498 180 259 84;
  • 30) 0.412 648 550 761 264 966 079 200 830 408 498 180 259 84 × 2 = 0 + 0.825 297 101 522 529 932 158 401 660 816 996 360 519 68;
  • 31) 0.825 297 101 522 529 932 158 401 660 816 996 360 519 68 × 2 = 1 + 0.650 594 203 045 059 864 316 803 321 633 992 721 039 36;
  • 32) 0.650 594 203 045 059 864 316 803 321 633 992 721 039 36 × 2 = 1 + 0.301 188 406 090 119 728 633 606 643 267 985 442 078 72;
  • 33) 0.301 188 406 090 119 728 633 606 643 267 985 442 078 72 × 2 = 0 + 0.602 376 812 180 239 457 267 213 286 535 970 884 157 44;
  • 34) 0.602 376 812 180 239 457 267 213 286 535 970 884 157 44 × 2 = 1 + 0.204 753 624 360 478 914 534 426 573 071 941 768 314 88;
  • 35) 0.204 753 624 360 478 914 534 426 573 071 941 768 314 88 × 2 = 0 + 0.409 507 248 720 957 829 068 853 146 143 883 536 629 76;
  • 36) 0.409 507 248 720 957 829 068 853 146 143 883 536 629 76 × 2 = 0 + 0.819 014 497 441 915 658 137 706 292 287 767 073 259 52;
  • 37) 0.819 014 497 441 915 658 137 706 292 287 767 073 259 52 × 2 = 1 + 0.638 028 994 883 831 316 275 412 584 575 534 146 519 04;
  • 38) 0.638 028 994 883 831 316 275 412 584 575 534 146 519 04 × 2 = 1 + 0.276 057 989 767 662 632 550 825 169 151 068 293 038 08;
  • 39) 0.276 057 989 767 662 632 550 825 169 151 068 293 038 08 × 2 = 0 + 0.552 115 979 535 325 265 101 650 338 302 136 586 076 16;
  • 40) 0.552 115 979 535 325 265 101 650 338 302 136 586 076 16 × 2 = 1 + 0.104 231 959 070 650 530 203 300 676 604 273 172 152 32;
  • 41) 0.104 231 959 070 650 530 203 300 676 604 273 172 152 32 × 2 = 0 + 0.208 463 918 141 301 060 406 601 353 208 546 344 304 64;
  • 42) 0.208 463 918 141 301 060 406 601 353 208 546 344 304 64 × 2 = 0 + 0.416 927 836 282 602 120 813 202 706 417 092 688 609 28;
  • 43) 0.416 927 836 282 602 120 813 202 706 417 092 688 609 28 × 2 = 0 + 0.833 855 672 565 204 241 626 405 412 834 185 377 218 56;
  • 44) 0.833 855 672 565 204 241 626 405 412 834 185 377 218 56 × 2 = 1 + 0.667 711 345 130 408 483 252 810 825 668 370 754 437 12;
  • 45) 0.667 711 345 130 408 483 252 810 825 668 370 754 437 12 × 2 = 1 + 0.335 422 690 260 816 966 505 621 651 336 741 508 874 24;
  • 46) 0.335 422 690 260 816 966 505 621 651 336 741 508 874 24 × 2 = 0 + 0.670 845 380 521 633 933 011 243 302 673 483 017 748 48;
  • 47) 0.670 845 380 521 633 933 011 243 302 673 483 017 748 48 × 2 = 1 + 0.341 690 761 043 267 866 022 486 605 346 966 035 496 96;
  • 48) 0.341 690 761 043 267 866 022 486 605 346 966 035 496 96 × 2 = 0 + 0.683 381 522 086 535 732 044 973 210 693 932 070 993 92;
  • 49) 0.683 381 522 086 535 732 044 973 210 693 932 070 993 92 × 2 = 1 + 0.366 763 044 173 071 464 089 946 421 387 864 141 987 84;
  • 50) 0.366 763 044 173 071 464 089 946 421 387 864 141 987 84 × 2 = 0 + 0.733 526 088 346 142 928 179 892 842 775 728 283 975 68;
  • 51) 0.733 526 088 346 142 928 179 892 842 775 728 283 975 68 × 2 = 1 + 0.467 052 176 692 285 856 359 785 685 551 456 567 951 36;
  • 52) 0.467 052 176 692 285 856 359 785 685 551 456 567 951 36 × 2 = 0 + 0.934 104 353 384 571 712 719 571 371 102 913 135 902 72;
  • 53) 0.934 104 353 384 571 712 719 571 371 102 913 135 902 72 × 2 = 1 + 0.868 208 706 769 143 425 439 142 742 205 826 271 805 44;
  • 54) 0.868 208 706 769 143 425 439 142 742 205 826 271 805 44 × 2 = 1 + 0.736 417 413 538 286 850 878 285 484 411 652 543 610 88;
  • 55) 0.736 417 413 538 286 850 878 285 484 411 652 543 610 88 × 2 = 1 + 0.472 834 827 076 573 701 756 570 968 823 305 087 221 76;
  • 56) 0.472 834 827 076 573 701 756 570 968 823 305 087 221 76 × 2 = 0 + 0.945 669 654 153 147 403 513 141 937 646 610 174 443 52;
  • 57) 0.945 669 654 153 147 403 513 141 937 646 610 174 443 52 × 2 = 1 + 0.891 339 308 306 294 807 026 283 875 293 220 348 887 04;
  • 58) 0.891 339 308 306 294 807 026 283 875 293 220 348 887 04 × 2 = 1 + 0.782 678 616 612 589 614 052 567 750 586 440 697 774 08;
  • 59) 0.782 678 616 612 589 614 052 567 750 586 440 697 774 08 × 2 = 1 + 0.565 357 233 225 179 228 105 135 501 172 881 395 548 16;
  • 60) 0.565 357 233 225 179 228 105 135 501 172 881 395 548 16 × 2 = 1 + 0.130 714 466 450 358 456 210 271 002 345 762 791 096 32;
  • 61) 0.130 714 466 450 358 456 210 271 002 345 762 791 096 32 × 2 = 0 + 0.261 428 932 900 716 912 420 542 004 691 525 582 192 64;
  • 62) 0.261 428 932 900 716 912 420 542 004 691 525 582 192 64 × 2 = 0 + 0.522 857 865 801 433 824 841 084 009 383 051 164 385 28;
  • 63) 0.522 857 865 801 433 824 841 084 009 383 051 164 385 28 × 2 = 1 + 0.045 715 731 602 867 649 682 168 018 766 102 328 770 56;
  • 64) 0.045 715 731 602 867 649 682 168 018 766 102 328 770 56 × 2 = 0 + 0.091 431 463 205 735 299 364 336 037 532 204 657 541 12;
  • 65) 0.091 431 463 205 735 299 364 336 037 532 204 657 541 12 × 2 = 0 + 0.182 862 926 411 470 598 728 672 075 064 409 315 082 24;
  • 66) 0.182 862 926 411 470 598 728 672 075 064 409 315 082 24 × 2 = 0 + 0.365 725 852 822 941 197 457 344 150 128 818 630 164 48;
  • 67) 0.365 725 852 822 941 197 457 344 150 128 818 630 164 48 × 2 = 0 + 0.731 451 705 645 882 394 914 688 300 257 637 260 328 96;
  • 68) 0.731 451 705 645 882 394 914 688 300 257 637 260 328 96 × 2 = 1 + 0.462 903 411 291 764 789 829 376 600 515 274 520 657 92;

We didn't get any fractional part that was equal to zero. But we had enough iterations (over Mantissa limit) and at least one integer that was different from zero => FULL STOP (Losing precision - the converted number we get in the end will be just a very good approximation of the initial one).


4. Construct the base 2 representation of the fractional part of the number.

Take all the integer parts of the multiplying operations, starting from the top of the constructed list above:


0.000 020 830 729 321 671 205 134 999 154 509 660 617 445(10) =


0.0000 0000 0000 0001 0101 1101 0111 1011 0100 1101 0001 1010 1010 1110 1111 0010 0001(2)

5. Positive number before normalization:

0.000 020 830 729 321 671 205 134 999 154 509 660 617 445(10) =


0.0000 0000 0000 0001 0101 1101 0111 1011 0100 1101 0001 1010 1010 1110 1111 0010 0001(2)

6. Normalize the binary representation of the number.

Shift the decimal mark 16 positions to the right, so that only one non zero digit remains to the left of it:


0.000 020 830 729 321 671 205 134 999 154 509 660 617 445(10) =


0.0000 0000 0000 0001 0101 1101 0111 1011 0100 1101 0001 1010 1010 1110 1111 0010 0001(2) =


0.0000 0000 0000 0001 0101 1101 0111 1011 0100 1101 0001 1010 1010 1110 1111 0010 0001(2) × 20 =


1.0101 1101 0111 1011 0100 1101 0001 1010 1010 1110 1111 0010 0001(2) × 2-16


7. Up to this moment, there are the following elements that would feed into the 64 bit double precision IEEE 754 binary floating point representation:

Sign 0 (a positive number)


Exponent (unadjusted): -16


Mantissa (not normalized):
1.0101 1101 0111 1011 0100 1101 0001 1010 1010 1110 1111 0010 0001


8. Adjust the exponent.

Use the 11 bit excess/bias notation:


Exponent (adjusted) =


Exponent (unadjusted) + 2(11-1) - 1 =


-16 + 2(11-1) - 1 =


(-16 + 1 023)(10) =


1 007(10)


9. Convert the adjusted exponent from the decimal (base 10) to 11 bit binary.

Use the same technique of repeatedly dividing by 2:


  • division = quotient + remainder;
  • 1 007 ÷ 2 = 503 + 1;
  • 503 ÷ 2 = 251 + 1;
  • 251 ÷ 2 = 125 + 1;
  • 125 ÷ 2 = 62 + 1;
  • 62 ÷ 2 = 31 + 0;
  • 31 ÷ 2 = 15 + 1;
  • 15 ÷ 2 = 7 + 1;
  • 7 ÷ 2 = 3 + 1;
  • 3 ÷ 2 = 1 + 1;
  • 1 ÷ 2 = 0 + 1;

10. Construct the base 2 representation of the adjusted exponent.

Take all the remainders starting from the bottom of the list constructed above.


Exponent (adjusted) =


1007(10) =


011 1110 1111(2)


11. Normalize the mantissa.

a) Remove the leading (the leftmost) bit, since it's allways 1, and the decimal point, if the case.


b) Adjust its length to 52 bits, only if necessary (not the case here).


Mantissa (normalized) =


1. 0101 1101 0111 1011 0100 1101 0001 1010 1010 1110 1111 0010 0001 =


0101 1101 0111 1011 0100 1101 0001 1010 1010 1110 1111 0010 0001


12. The three elements that make up the number's 64 bit double precision IEEE 754 binary floating point representation:

Sign (1 bit) =
0 (a positive number)


Exponent (11 bits) =
011 1110 1111


Mantissa (52 bits) =
0101 1101 0111 1011 0100 1101 0001 1010 1010 1110 1111 0010 0001


Decimal number 0.000 020 830 729 321 671 205 134 999 154 509 660 617 445 converted to 64 bit double precision IEEE 754 binary floating point representation:

0 - 011 1110 1111 - 0101 1101 0111 1011 0100 1101 0001 1010 1010 1110 1111 0010 0001


How to convert numbers from the decimal system (base ten) to 64 bit double precision IEEE 754 binary floating point standard

Follow the steps below to convert a base 10 decimal number to 64 bit double precision IEEE 754 binary floating point:

  • 1. If the number to be converted is negative, start with its the positive version.
  • 2. First convert the integer part. Divide repeatedly by 2 the positive representation of the integer number that is to be converted to binary, until we get a quotient that is equal to zero, keeping track of each remainder.
  • 3. Construct the base 2 representation of the positive integer part of the number, by taking all the remainders from the previous operations, starting from the bottom of the list constructed above. Thus, the last remainder of the divisions becomes the first symbol (the leftmost) of the base two number, while the first remainder becomes the last symbol (the rightmost).
  • 4. Then convert the fractional part. Multiply the number repeatedly by 2, until we get a fractional part that is equal to zero, keeping track of each integer part of the results.
  • 5. Construct the base 2 representation of the fractional part of the number, by taking all the integer parts of the multiplying operations, starting from the top of the list constructed above (they should appear in the binary representation, from left to right, in the order they have been calculated).
  • 6. Normalize the binary representation of the number, shifting the decimal mark (the decimal point) "n" positions either to the left, or to the right, so that only one non zero digit remains to the left of the decimal mark.
  • 7. Adjust the exponent in 11 bit excess/bias notation and then convert it from decimal (base 10) to 11 bit binary, by using the same technique of repeatedly dividing by 2, as shown above:
    Exponent (adjusted) = Exponent (unadjusted) + 2(11-1) - 1
  • 8. Normalize mantissa, remove the leading (leftmost) bit, since it's allways '1' (and the decimal mark, if the case) and adjust its length to 52 bits, either by removing the excess bits from the right (losing precision...) or by adding extra bits set on '0' to the right.
  • 9. Sign (it takes 1 bit) is either 1 for a negative or 0 for a positive number.

Example: convert the negative number -31.640 215 from the decimal system (base ten) to 64 bit double precision IEEE 754 binary floating point:

  • 1. Start with the positive version of the number:

    |-31.640 215| = 31.640 215

  • 2. First convert the integer part, 31. Divide it repeatedly by 2, keeping track of each remainder, until we get a quotient that is equal to zero:
    • division = quotient + remainder;
    • 31 ÷ 2 = 15 + 1;
    • 15 ÷ 2 = 7 + 1;
    • 7 ÷ 2 = 3 + 1;
    • 3 ÷ 2 = 1 + 1;
    • 1 ÷ 2 = 0 + 1;
    • We have encountered a quotient that is ZERO => FULL STOP
  • 3. Construct the base 2 representation of the integer part of the number by taking all the remainders of the previous dividing operations, starting from the bottom of the list constructed above:

    31(10) = 1 1111(2)

  • 4. Then, convert the fractional part, 0.640 215. Multiply repeatedly by 2, keeping track of each integer part of the results, until we get a fractional part that is equal to zero:
    • #) multiplying = integer + fractional part;
    • 1) 0.640 215 × 2 = 1 + 0.280 43;
    • 2) 0.280 43 × 2 = 0 + 0.560 86;
    • 3) 0.560 86 × 2 = 1 + 0.121 72;
    • 4) 0.121 72 × 2 = 0 + 0.243 44;
    • 5) 0.243 44 × 2 = 0 + 0.486 88;
    • 6) 0.486 88 × 2 = 0 + 0.973 76;
    • 7) 0.973 76 × 2 = 1 + 0.947 52;
    • 8) 0.947 52 × 2 = 1 + 0.895 04;
    • 9) 0.895 04 × 2 = 1 + 0.790 08;
    • 10) 0.790 08 × 2 = 1 + 0.580 16;
    • 11) 0.580 16 × 2 = 1 + 0.160 32;
    • 12) 0.160 32 × 2 = 0 + 0.320 64;
    • 13) 0.320 64 × 2 = 0 + 0.641 28;
    • 14) 0.641 28 × 2 = 1 + 0.282 56;
    • 15) 0.282 56 × 2 = 0 + 0.565 12;
    • 16) 0.565 12 × 2 = 1 + 0.130 24;
    • 17) 0.130 24 × 2 = 0 + 0.260 48;
    • 18) 0.260 48 × 2 = 0 + 0.520 96;
    • 19) 0.520 96 × 2 = 1 + 0.041 92;
    • 20) 0.041 92 × 2 = 0 + 0.083 84;
    • 21) 0.083 84 × 2 = 0 + 0.167 68;
    • 22) 0.167 68 × 2 = 0 + 0.335 36;
    • 23) 0.335 36 × 2 = 0 + 0.670 72;
    • 24) 0.670 72 × 2 = 1 + 0.341 44;
    • 25) 0.341 44 × 2 = 0 + 0.682 88;
    • 26) 0.682 88 × 2 = 1 + 0.365 76;
    • 27) 0.365 76 × 2 = 0 + 0.731 52;
    • 28) 0.731 52 × 2 = 1 + 0.463 04;
    • 29) 0.463 04 × 2 = 0 + 0.926 08;
    • 30) 0.926 08 × 2 = 1 + 0.852 16;
    • 31) 0.852 16 × 2 = 1 + 0.704 32;
    • 32) 0.704 32 × 2 = 1 + 0.408 64;
    • 33) 0.408 64 × 2 = 0 + 0.817 28;
    • 34) 0.817 28 × 2 = 1 + 0.634 56;
    • 35) 0.634 56 × 2 = 1 + 0.269 12;
    • 36) 0.269 12 × 2 = 0 + 0.538 24;
    • 37) 0.538 24 × 2 = 1 + 0.076 48;
    • 38) 0.076 48 × 2 = 0 + 0.152 96;
    • 39) 0.152 96 × 2 = 0 + 0.305 92;
    • 40) 0.305 92 × 2 = 0 + 0.611 84;
    • 41) 0.611 84 × 2 = 1 + 0.223 68;
    • 42) 0.223 68 × 2 = 0 + 0.447 36;
    • 43) 0.447 36 × 2 = 0 + 0.894 72;
    • 44) 0.894 72 × 2 = 1 + 0.789 44;
    • 45) 0.789 44 × 2 = 1 + 0.578 88;
    • 46) 0.578 88 × 2 = 1 + 0.157 76;
    • 47) 0.157 76 × 2 = 0 + 0.315 52;
    • 48) 0.315 52 × 2 = 0 + 0.631 04;
    • 49) 0.631 04 × 2 = 1 + 0.262 08;
    • 50) 0.262 08 × 2 = 0 + 0.524 16;
    • 51) 0.524 16 × 2 = 1 + 0.048 32;
    • 52) 0.048 32 × 2 = 0 + 0.096 64;
    • 53) 0.096 64 × 2 = 0 + 0.193 28;
    • We didn't get any fractional part that was equal to zero. But we had enough iterations (over Mantissa limit = 52) and at least one integer part that was different from zero => FULL STOP (losing precision...).
  • 5. Construct the base 2 representation of the fractional part of the number, by taking all the integer parts of the previous multiplying operations, starting from the top of the constructed list above:

    0.640 215(10) = 0.1010 0011 1110 0101 0010 0001 0101 0111 0110 1000 1001 1100 1010 0(2)

  • 6. Summarizing - the positive number before normalization:

    31.640 215(10) = 1 1111.1010 0011 1110 0101 0010 0001 0101 0111 0110 1000 1001 1100 1010 0(2)

  • 7. Normalize the binary representation of the number, shifting the decimal mark 4 positions to the left so that only one non-zero digit stays to the left of the decimal mark:

    31.640 215(10) =
    1 1111.1010 0011 1110 0101 0010 0001 0101 0111 0110 1000 1001 1100 1010 0(2) =
    1 1111.1010 0011 1110 0101 0010 0001 0101 0111 0110 1000 1001 1100 1010 0(2) × 20 =
    1.1111 1010 0011 1110 0101 0010 0001 0101 0111 0110 1000 1001 1100 1010 0(2) × 24

  • 8. Up to this moment, there are the following elements that would feed into the 64 bit double precision IEEE 754 binary floating point representation:

    Sign: 1 (a negative number)

    Exponent (unadjusted): 4

    Mantissa (not-normalized): 1.1111 1010 0011 1110 0101 0010 0001 0101 0111 0110 1000 1001 1100 1010 0

  • 9. Adjust the exponent in 11 bit excess/bias notation and then convert it from decimal (base 10) to 11 bit binary (base 2), by using the same technique of repeatedly dividing it by 2, as shown above:

    Exponent (adjusted) = Exponent (unadjusted) + 2(11-1) - 1 = (4 + 1023)(10) = 1027(10) =
    100 0000 0011(2)

  • 10. Normalize mantissa, remove the leading (leftmost) bit, since it's allways '1' (and the decimal sign) and adjust its length to 52 bits, by removing the excess bits, from the right (losing precision...):

    Mantissa (not-normalized): 1.1111 1010 0011 1110 0101 0010 0001 0101 0111 0110 1000 1001 1100 1010 0

    Mantissa (normalized): 1111 1010 0011 1110 0101 0010 0001 0101 0111 0110 1000 1001 1100

  • Conclusion:

    Sign (1 bit) = 1 (a negative number)

    Exponent (8 bits) = 100 0000 0011

    Mantissa (52 bits) = 1111 1010 0011 1110 0101 0010 0001 0101 0111 0110 1000 1001 1100

  • Number -31.640 215, converted from decimal system (base 10) to 64 bit double precision IEEE 754 binary floating point =
    1 - 100 0000 0011 - 1111 1010 0011 1110 0101 0010 0001 0101 0111 0110 1000 1001 1100