1 - 111 1110 1101 - 1100 1011 1010 0000 1001 1000 0111 0110 0101 0100 0011 0110 1101 64 Bit Double Precision IEEE 754 Binary Floating Point Representation Standard Converted to Decimal
1 - 111 1110 1101 - 1100 1011 1010 0000 1001 1000 0111 0110 0101 0100 0011 0110 1101: 64 bit double precision IEEE 754 binary floating point representation standard converted to decimal
What are the steps to convert
1 - 111 1110 1101 - 1100 1011 1010 0000 1001 1000 0111 0110 0101 0100 0011 0110 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 1110 1101
The last 52 bits contain the mantissa:
1100 1011 1010 0000 1001 1000 0111 0110 0101 0100 0011 0110 1101
2. Convert the exponent from binary (from base 2) to decimal (in base 10).
The exponent is allways a positive integer.
111 1110 1101(2) =
1 × 210 + 1 × 29 + 1 × 28 + 1 × 27 + 1 × 26 + 1 × 25 + 0 × 24 + 1 × 23 + 1 × 22 + 0 × 21 + 1 × 20 =
1,024 + 512 + 256 + 128 + 64 + 32 + 0 + 8 + 4 + 0 + 1 =
1,024 + 512 + 256 + 128 + 64 + 32 + 8 + 4 + 1 =
2,029(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 = 2,029 - 1023 = 1006
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).
1100 1011 1010 0000 1001 1000 0111 0110 0101 0100 0011 0110 1101(2) =
1 × 2-1 + 1 × 2-2 + 0 × 2-3 + 0 × 2-4 + 1 × 2-5 + 0 × 2-6 + 1 × 2-7 + 1 × 2-8 + 1 × 2-9 + 0 × 2-10 + 1 × 2-11 + 0 × 2-12 + 0 × 2-13 + 0 × 2-14 + 0 × 2-15 + 0 × 2-16 + 1 × 2-17 + 0 × 2-18 + 0 × 2-19 + 1 × 2-20 + 1 × 2-21 + 0 × 2-22 + 0 × 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 + 1 × 2-34 + 0 × 2-35 + 1 × 2-36 + 0 × 2-37 + 1 × 2-38 + 0 × 2-39 + 0 × 2-40 + 0 × 2-41 + 0 × 2-42 + 1 × 2-43 + 1 × 2-44 + 0 × 2-45 + 1 × 2-46 + 1 × 2-47 + 0 × 2-48 + 1 × 2-49 + 1 × 2-50 + 0 × 2-51 + 1 × 2-52 =
0.5 + 0.25 + 0 + 0 + 0.031 25 + 0 + 0.007 812 5 + 0.003 906 25 + 0.001 953 125 + 0 + 0.000 488 281 25 + 0 + 0 + 0 + 0 + 0 + 0.000 007 629 394 531 25 + 0 + 0 + 0.000 000 953 674 316 406 25 + 0.000 000 476 837 158 203 125 + 0 + 0 + 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 + 0.000 000 000 058 207 660 913 467 407 226 562 5 + 0 + 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 + 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 + 0.000 000 000 000 007 105 427 357 601 001 858 711 242 675 781 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 + 0.25 + 0.031 25 + 0.007 812 5 + 0.003 906 25 + 0.001 953 125 + 0.000 488 281 25 + 0.000 007 629 394 531 25 + 0.000 000 953 674 316 406 25 + 0.000 000 476 837 158 203 125 + 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 + 0.000 000 000 058 207 660 913 467 407 226 562 5 + 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 + 0.000 000 000 000 113 686 837 721 616 029 739 379 882 812 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 + 0.000 000 000 000 007 105 427 357 601 001 858 711 242 675 781 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 =
0.795 419 243 706 614 098 599 061 435 379 553 586 244 583 129 882 812 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 + 0.795 419 243 706 614 098 599 061 435 379 553 586 244 583 129 882 812 5) × 21006 =
-1.795 419 243 706 614 098 599 061 435 379 553 586 244 583 129 882 812 5 × 21006 = ...
= -1 231 236 590 809 277 134 067 788 434 462 045 267 833 203 770 009 298 365 858 550 760 242 274 767 528 306 393 254 828 234 520 202 471 911 083 686 787 610 625 066 554 040 431 441 677 527 011 590 103 675 241 349 309 379 844 673 899 677 593 154 927 250 802 335 252 817 267 414 809 330 751 504 162 134 052 541 951 657 062 324 969 681 094 136 203 327 802 464 068 727 170 573 839 874 144 358 343 025 832 755 200
1 - 111 1110 1101 - 1100 1011 1010 0000 1001 1000 0111 0110 0101 0100 0011 0110 1101, a 64 bit double precision IEEE 754 binary floating point representation standard to a decimal number, written in base ten (double) = -1 231 236 590 809 277 134 067 788 434 462 045 267 833 203 770 009 298 365 858 550 760 242 274 767 528 306 393 254 828 234 520 202 471 911 083 686 787 610 625 066 554 040 431 441 677 527 011 590 103 675 241 349 309 379 844 673 899 677 593 154 927 250 802 335 252 817 267 414 809 330 751 504 162 134 052 541 951 657 062 324 969 681 094 136 203 327 802 464 068 727 170 573 839 874 144 358 343 025 832 755 200(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.