1 - 110 0011 1101 - 0100 1110 0111 0011 1001 1100 1110 0111 0011 1001 1101 0001 0000 64 Bit Double Precision IEEE 754 Binary Floating Point Representation Standard Converted to Decimal
1 - 110 0011 1101 - 0100 1110 0111 0011 1001 1100 1110 0111 0011 1001 1101 0001 0000: 64 bit double precision IEEE 754 binary floating point representation standard converted to decimal
What are the steps to convert
1 - 110 0011 1101 - 0100 1110 0111 0011 1001 1100 1110 0111 0011 1001 1101 0001 0000, 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:
110 0011 1101
The last 52 bits contain the mantissa:
0100 1110 0111 0011 1001 1100 1110 0111 0011 1001 1101 0001 0000
2. Convert the exponent from binary (from base 2) to decimal (in base 10).
The exponent is allways a positive integer.
110 0011 1101(2) =
1 × 210 + 1 × 29 + 0 × 28 + 0 × 27 + 0 × 26 + 1 × 25 + 1 × 24 + 1 × 23 + 1 × 22 + 0 × 21 + 1 × 20 =
1,024 + 512 + 0 + 0 + 0 + 32 + 16 + 8 + 4 + 0 + 1 =
1,024 + 512 + 32 + 16 + 8 + 4 + 1 =
1,597(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 = 1,597 - 1023 = 574
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 1110 0111 0011 1001 1100 1110 0111 0011 1001 1101 0001 0000(2) =
0 × 2-1 + 1 × 2-2 + 0 × 2-3 + 0 × 2-4 + 1 × 2-5 + 1 × 2-6 + 1 × 2-7 + 0 × 2-8 + 0 × 2-9 + 1 × 2-10 + 1 × 2-11 + 1 × 2-12 + 0 × 2-13 + 0 × 2-14 + 1 × 2-15 + 1 × 2-16 + 1 × 2-17 + 0 × 2-18 + 0 × 2-19 + 1 × 2-20 + 1 × 2-21 + 1 × 2-22 + 0 × 2-23 + 0 × 2-24 + 1 × 2-25 + 1 × 2-26 + 1 × 2-27 + 0 × 2-28 + 0 × 2-29 + 1 × 2-30 + 1 × 2-31 + 1 × 2-32 + 0 × 2-33 + 0 × 2-34 + 1 × 2-35 + 1 × 2-36 + 1 × 2-37 + 0 × 2-38 + 0 × 2-39 + 1 × 2-40 + 1 × 2-41 + 1 × 2-42 + 0 × 2-43 + 1 × 2-44 + 0 × 2-45 + 0 × 2-46 + 0 × 2-47 + 1 × 2-48 + 0 × 2-49 + 0 × 2-50 + 0 × 2-51 + 0 × 2-52 =
0 + 0.25 + 0 + 0 + 0.031 25 + 0.015 625 + 0.007 812 5 + 0 + 0 + 0.000 976 562 5 + 0.000 488 281 25 + 0.000 244 140 625 + 0 + 0 + 0.000 030 517 578 125 + 0.000 015 258 789 062 5 + 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 + 0.000 000 238 418 579 101 562 5 + 0 + 0 + 0.000 000 029 802 322 387 695 312 5 + 0.000 000 014 901 161 193 847 656 25 + 0.000 000 007 450 580 596 923 828 125 + 0 + 0 + 0.000 000 000 931 322 574 615 478 515 625 + 0.000 000 000 465 661 287 307 739 257 812 5 + 0.000 000 000 232 830 643 653 869 628 906 25 + 0 + 0 + 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 + 0.000 000 000 007 275 957 614 183 425 903 320 312 5 + 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 + 0.000 000 000 000 227 373 675 443 232 059 478 759 765 625 + 0 + 0.000 000 000 000 056 843 418 860 808 014 869 689 941 406 25 + 0 + 0 + 0 + 0.000 000 000 000 003 552 713 678 800 500 929 355 621 337 890 625 + 0 + 0 + 0 + 0 =
0.25 + 0.031 25 + 0.015 625 + 0.007 812 5 + 0.000 976 562 5 + 0.000 488 281 25 + 0.000 244 140 625 + 0.000 030 517 578 125 + 0.000 015 258 789 062 5 + 0.000 007 629 394 531 25 + 0.000 000 953 674 316 406 25 + 0.000 000 476 837 158 203 125 + 0.000 000 238 418 579 101 562 5 + 0.000 000 029 802 322 387 695 312 5 + 0.000 000 014 901 161 193 847 656 25 + 0.000 000 007 450 580 596 923 828 125 + 0.000 000 000 931 322 574 615 478 515 625 + 0.000 000 000 465 661 287 307 739 257 812 5 + 0.000 000 000 232 830 643 653 869 628 906 25 + 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 + 0.000 000 000 007 275 957 614 183 425 903 320 312 5 + 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 + 0.000 000 000 000 227 373 675 443 232 059 478 759 765 625 + 0.000 000 000 000 056 843 418 860 808 014 869 689 941 406 25 + 0.000 000 000 000 003 552 713 678 800 500 929 355 621 337 890 625 =
0.306 451 612 903 234 860 141 310 491 599 142 551 422 119 140 625(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 + 0.306 451 612 903 234 860 141 310 491 599 142 551 422 119 140 625) × 2574 =
-1.306 451 612 903 234 860 141 310 491 599 142 551 422 119 140 625 × 2574 = ...
= -80 781 300 481 135 508 437 776 543 080 815 718 495 191 128 626 187 843 105 236 361 458 601 914 626 040 644 392 020 038 387 728 567 624 208 000 495 017 044 948 903 476 407 611 773 349 848 615 100 131 684 726 203 198 822 802 259 968
1 - 110 0011 1101 - 0100 1110 0111 0011 1001 1100 1110 0111 0011 1001 1101 0001 0000, a 64 bit double precision IEEE 754 binary floating point representation standard to a decimal number, written in base ten (double) = -80 781 300 481 135 508 437 776 543 080 815 718 495 191 128 626 187 843 105 236 361 458 601 914 626 040 644 392 020 038 387 728 567 624 208 000 495 017 044 948 903 476 407 611 773 349 848 615 100 131 684 726 203 198 822 802 259 968(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.