1 - 111 1011 1111 - 0111 0110 0101 1110 0111 1010 0010 1010 1101 0000 1010 1000 0010 64 Bit Double Precision IEEE 754 Binary Floating Point Representation Standard Converted to Decimal
1 - 111 1011 1111 - 0111 0110 0101 1110 0111 1010 0010 1010 1101 0000 1010 1000 0010: 64 bit double precision IEEE 754 binary floating point representation standard converted to decimal
What are the steps to convert
1 - 111 1011 1111 - 0111 0110 0101 1110 0111 1010 0010 1010 1101 0000 1010 1000 0010, 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 1011 1111
The last 52 bits contain the mantissa:
0111 0110 0101 1110 0111 1010 0010 1010 1101 0000 1010 1000 0010
2. Convert the exponent from binary (from base 2) to decimal (in base 10).
The exponent is allways a positive integer.
111 1011 1111(2) =
1 × 210 + 1 × 29 + 1 × 28 + 1 × 27 + 0 × 26 + 1 × 25 + 1 × 24 + 1 × 23 + 1 × 22 + 1 × 21 + 1 × 20 =
1,024 + 512 + 256 + 128 + 0 + 32 + 16 + 8 + 4 + 2 + 1 =
1,024 + 512 + 256 + 128 + 32 + 16 + 8 + 4 + 2 + 1 =
1,983(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 = 1,983 - 1023 = 960
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).
0111 0110 0101 1110 0111 1010 0010 1010 1101 0000 1010 1000 0010(2) =
0 × 2-1 + 1 × 2-2 + 1 × 2-3 + 1 × 2-4 + 0 × 2-5 + 1 × 2-6 + 1 × 2-7 + 0 × 2-8 + 0 × 2-9 + 1 × 2-10 + 0 × 2-11 + 1 × 2-12 + 1 × 2-13 + 1 × 2-14 + 1 × 2-15 + 0 × 2-16 + 0 × 2-17 + 1 × 2-18 + 1 × 2-19 + 1 × 2-20 + 1 × 2-21 + 0 × 2-22 + 1 × 2-23 + 0 × 2-24 + 0 × 2-25 + 0 × 2-26 + 1 × 2-27 + 0 × 2-28 + 1 × 2-29 + 0 × 2-30 + 1 × 2-31 + 0 × 2-32 + 1 × 2-33 + 1 × 2-34 + 0 × 2-35 + 1 × 2-36 + 0 × 2-37 + 0 × 2-38 + 0 × 2-39 + 0 × 2-40 + 1 × 2-41 + 0 × 2-42 + 1 × 2-43 + 0 × 2-44 + 1 × 2-45 + 0 × 2-46 + 0 × 2-47 + 0 × 2-48 + 0 × 2-49 + 0 × 2-50 + 1 × 2-51 + 0 × 2-52 =
0 + 0.25 + 0.125 + 0.062 5 + 0 + 0.015 625 + 0.007 812 5 + 0 + 0 + 0.000 976 562 5 + 0 + 0.000 244 140 625 + 0.000 122 070 312 5 + 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 + 0.000 000 953 674 316 406 25 + 0.000 000 476 837 158 203 125 + 0 + 0.000 000 119 209 289 550 781 25 + 0 + 0 + 0 + 0.000 000 007 450 580 596 923 828 125 + 0 + 0.000 000 001 862 645 149 230 957 031 25 + 0 + 0.000 000 000 465 661 287 307 739 257 812 5 + 0 + 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 + 0.000 000 000 014 551 915 228 366 851 806 640 625 + 0 + 0 + 0 + 0 + 0.000 000 000 000 454 747 350 886 464 118 957 519 531 25 + 0 + 0.000 000 000 000 113 686 837 721 616 029 739 379 882 812 5 + 0 + 0.000 000 000 000 028 421 709 430 404 007 434 844 970 703 125 + 0 + 0 + 0 + 0 + 0 + 0.000 000 000 000 000 444 089 209 850 062 616 169 452 667 236 328 125 + 0 =
0.25 + 0.125 + 0.062 5 + 0.015 625 + 0.007 812 5 + 0.000 976 562 5 + 0.000 244 140 625 + 0.000 122 070 312 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 + 0.000 000 953 674 316 406 25 + 0.000 000 476 837 158 203 125 + 0.000 000 119 209 289 550 781 25 + 0.000 000 007 450 580 596 923 828 125 + 0.000 000 001 862 645 149 230 957 031 25 + 0.000 000 000 465 661 287 307 739 257 812 5 + 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 + 0.000 000 000 014 551 915 228 366 851 806 640 625 + 0.000 000 000 000 454 747 350 886 464 118 957 519 531 25 + 0.000 000 000 000 113 686 837 721 616 029 739 379 882 812 5 + 0.000 000 000 000 028 421 709 430 404 007 434 844 970 703 125 + 0.000 000 000 000 000 444 089 209 850 062 616 169 452 667 236 328 125 =
0.462 379 107 907 196 829 074 791 821 767 576 038 837 432 861 328 125(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 + 0.462 379 107 907 196 829 074 791 821 767 576 038 837 432 861 328 125) × 2960 =
-1.462 379 107 907 196 829 074 791 821 767 576 038 837 432 861 328 125 × 2960 = ...
= -14 251 343 610 266 636 444 408 219 385 719 640 427 936 133 019 651 558 044 415 082 943 265 511 722 389 542 054 501 309 873 403 921 090 072 387 696 956 282 474 914 988 664 812 101 652 136 541 923 810 103 556 250 856 035 042 825 503 151 015 211 614 376 753 334 720 704 861 595 532 676 044 815 415 512 678 621 701 091 157 531 781 201 658 171 440 255 957 956 536 460 712 982 278 569 984 000
1 - 111 1011 1111 - 0111 0110 0101 1110 0111 1010 0010 1010 1101 0000 1010 1000 0010, a 64 bit double precision IEEE 754 binary floating point representation standard to a decimal number, written in base ten (double) = -14 251 343 610 266 636 444 408 219 385 719 640 427 936 133 019 651 558 044 415 082 943 265 511 722 389 542 054 501 309 873 403 921 090 072 387 696 956 282 474 914 988 664 812 101 652 136 541 923 810 103 556 250 856 035 042 825 503 151 015 211 614 376 753 334 720 704 861 595 532 676 044 815 415 512 678 621 701 091 157 531 781 201 658 171 440 255 957 956 536 460 712 982 278 569 984 000(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.