1 - 011 1001 1001 - 0110 0100 1100 0110 0110 0100 0110 0110 0001 1001 1110 0101 1010 64 Bit Double Precision IEEE 754 Binary Floating Point Representation Standard Converted to Decimal
1 - 011 1001 1001 - 0110 0100 1100 0110 0110 0100 0110 0110 0001 1001 1110 0101 1010: 64 bit double precision IEEE 754 binary floating point representation standard converted to decimal
What are the steps to convert
1 - 011 1001 1001 - 0110 0100 1100 0110 0110 0100 0110 0110 0001 1001 1110 0101 1010, 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:
011 1001 1001
The last 52 bits contain the mantissa:
0110 0100 1100 0110 0110 0100 0110 0110 0001 1001 1110 0101 1010
2. Convert the exponent from binary (from base 2) to decimal (in base 10).
The exponent is allways a positive integer.
011 1001 1001(2) =
0 × 210 + 1 × 29 + 1 × 28 + 1 × 27 + 0 × 26 + 0 × 25 + 1 × 24 + 1 × 23 + 0 × 22 + 0 × 21 + 1 × 20 =
0 + 512 + 256 + 128 + 0 + 0 + 16 + 8 + 0 + 0 + 1 =
512 + 256 + 128 + 16 + 8 + 1 =
921(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 = 921 - 1023 = -102
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).
0110 0100 1100 0110 0110 0100 0110 0110 0001 1001 1110 0101 1010(2) =
0 × 2-1 + 1 × 2-2 + 1 × 2-3 + 0 × 2-4 + 0 × 2-5 + 1 × 2-6 + 0 × 2-7 + 0 × 2-8 + 1 × 2-9 + 1 × 2-10 + 0 × 2-11 + 0 × 2-12 + 0 × 2-13 + 1 × 2-14 + 1 × 2-15 + 0 × 2-16 + 0 × 2-17 + 1 × 2-18 + 1 × 2-19 + 0 × 2-20 + 0 × 2-21 + 1 × 2-22 + 0 × 2-23 + 0 × 2-24 + 0 × 2-25 + 1 × 2-26 + 1 × 2-27 + 0 × 2-28 + 0 × 2-29 + 1 × 2-30 + 1 × 2-31 + 0 × 2-32 + 0 × 2-33 + 0 × 2-34 + 0 × 2-35 + 1 × 2-36 + 1 × 2-37 + 0 × 2-38 + 0 × 2-39 + 1 × 2-40 + 1 × 2-41 + 1 × 2-42 + 1 × 2-43 + 0 × 2-44 + 0 × 2-45 + 1 × 2-46 + 0 × 2-47 + 1 × 2-48 + 1 × 2-49 + 0 × 2-50 + 1 × 2-51 + 0 × 2-52 =
0 + 0.25 + 0.125 + 0 + 0 + 0.015 625 + 0 + 0 + 0.001 953 125 + 0.000 976 562 5 + 0 + 0 + 0 + 0.000 061 035 156 25 + 0.000 030 517 578 125 + 0 + 0 + 0.000 003 814 697 265 625 + 0.000 001 907 348 632 812 5 + 0 + 0 + 0.000 000 238 418 579 101 562 5 + 0 + 0 + 0 + 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 + 0 + 0 + 0 + 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 + 0.000 000 000 000 113 686 837 721 616 029 739 379 882 812 5 + 0 + 0 + 0.000 000 000 000 014 210 854 715 202 003 717 422 485 351 562 5 + 0 + 0.000 000 000 000 003 552 713 678 800 500 929 355 621 337 890 625 + 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 =
0.25 + 0.125 + 0.015 625 + 0.001 953 125 + 0.000 976 562 5 + 0.000 061 035 156 25 + 0.000 030 517 578 125 + 0.000 003 814 697 265 625 + 0.000 001 907 348 632 812 5 + 0.000 000 238 418 579 101 562 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 + 0.000 000 000 014 551 915 228 366 851 806 640 625 + 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 + 0.000 000 000 000 113 686 837 721 616 029 739 379 882 812 5 + 0.000 000 000 000 014 210 854 715 202 003 717 422 485 351 562 5 + 0.000 000 000 000 003 552 713 678 800 500 929 355 621 337 890 625 + 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 =
0.393 652 224 471 131 351 180 019 919 411 279 261 112 213 134 765 625(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 + 0.393 652 224 471 131 351 180 019 919 411 279 261 112 213 134 765 625) × 2-102 =
-1.393 652 224 471 131 351 180 019 919 411 279 261 112 213 134 765 625 × 2-102 = ...
= -0.000 000 000 000 000 000 000 000 000 000 274 849 438 839 893 354 578 044 918 186 464 090 158 870 546 243 509 717 864 583 915 753 362 717 687 217 063 079 752 055 188 009 762 787 260 115 146 636 962 890 625
1 - 011 1001 1001 - 0110 0100 1100 0110 0110 0100 0110 0110 0001 1001 1110 0101 1010, a 64 bit double precision IEEE 754 binary floating point representation standard to a decimal number, written in base ten (double) = -0.000 000 000 000 000 000 000 000 000 000 274 849 438 839 893 354 578 044 918 186 464 090 158 870 546 243 509 717 864 583 915 753 362 717 687 217 063 079 752 055 188 009 762 787 260 115 146 636 962 890 625(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.