0 - 111 1100 0100 - 0011 0101 0011 0011 0011 0011 0010 0011 0001 0011 0100 1000 1110 64 Bit Double Precision IEEE 754 Binary Floating Point Representation Standard Converted to Decimal
0 - 111 1100 0100 - 0011 0101 0011 0011 0011 0011 0010 0011 0001 0011 0100 1000 1110: 64 bit double precision IEEE 754 binary floating point representation standard converted to decimal
What are the steps to convert
0 - 111 1100 0100 - 0011 0101 0011 0011 0011 0011 0010 0011 0001 0011 0100 1000 1110, 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.
0
The next 11 bits contain the exponent:
111 1100 0100
The last 52 bits contain the mantissa:
0011 0101 0011 0011 0011 0011 0010 0011 0001 0011 0100 1000 1110
2. Convert the exponent from binary (from base 2) to decimal (in base 10).
The exponent is allways a positive integer.
111 1100 0100(2) =
1 × 210 + 1 × 29 + 1 × 28 + 1 × 27 + 1 × 26 + 0 × 25 + 0 × 24 + 0 × 23 + 1 × 22 + 0 × 21 + 0 × 20 =
1,024 + 512 + 256 + 128 + 64 + 0 + 0 + 0 + 4 + 0 + 0 =
1,024 + 512 + 256 + 128 + 64 + 4 =
1,988(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 = 1,988 - 1023 = 965
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).
0011 0101 0011 0011 0011 0011 0010 0011 0001 0011 0100 1000 1110(2) =
0 × 2-1 + 0 × 2-2 + 1 × 2-3 + 1 × 2-4 + 0 × 2-5 + 1 × 2-6 + 0 × 2-7 + 1 × 2-8 + 0 × 2-9 + 0 × 2-10 + 1 × 2-11 + 1 × 2-12 + 0 × 2-13 + 0 × 2-14 + 1 × 2-15 + 1 × 2-16 + 0 × 2-17 + 0 × 2-18 + 1 × 2-19 + 1 × 2-20 + 0 × 2-21 + 0 × 2-22 + 1 × 2-23 + 1 × 2-24 + 0 × 2-25 + 0 × 2-26 + 1 × 2-27 + 0 × 2-28 + 0 × 2-29 + 0 × 2-30 + 1 × 2-31 + 1 × 2-32 + 0 × 2-33 + 0 × 2-34 + 0 × 2-35 + 1 × 2-36 + 0 × 2-37 + 0 × 2-38 + 1 × 2-39 + 1 × 2-40 + 0 × 2-41 + 1 × 2-42 + 0 × 2-43 + 0 × 2-44 + 1 × 2-45 + 0 × 2-46 + 0 × 2-47 + 0 × 2-48 + 1 × 2-49 + 1 × 2-50 + 1 × 2-51 + 0 × 2-52 =
0 + 0 + 0.125 + 0.062 5 + 0 + 0.015 625 + 0 + 0.003 906 25 + 0 + 0 + 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 + 0 + 0.000 001 907 348 632 812 5 + 0.000 000 953 674 316 406 25 + 0 + 0 + 0.000 000 119 209 289 550 781 25 + 0.000 000 059 604 644 775 390 625 + 0 + 0 + 0.000 000 007 450 580 596 923 828 125 + 0 + 0 + 0 + 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 + 0.000 000 000 014 551 915 228 366 851 806 640 625 + 0 + 0 + 0.000 000 000 001 818 989 403 545 856 475 830 078 125 + 0.000 000 000 000 909 494 701 772 928 237 915 039 062 5 + 0 + 0.000 000 000 000 227 373 675 443 232 059 478 759 765 625 + 0 + 0 + 0.000 000 000 000 028 421 709 430 404 007 434 844 970 703 125 + 0 + 0 + 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 + 0.000 000 000 000 000 444 089 209 850 062 616 169 452 667 236 328 125 + 0 =
0.125 + 0.062 5 + 0.015 625 + 0.003 906 25 + 0.000 488 281 25 + 0.000 244 140 625 + 0.000 030 517 578 125 + 0.000 015 258 789 062 5 + 0.000 001 907 348 632 812 5 + 0.000 000 953 674 316 406 25 + 0.000 000 119 209 289 550 781 25 + 0.000 000 059 604 644 775 390 625 + 0.000 000 007 450 580 596 923 828 125 + 0.000 000 000 465 661 287 307 739 257 812 5 + 0.000 000 000 232 830 643 653 869 628 906 25 + 0.000 000 000 014 551 915 228 366 851 806 640 625 + 0.000 000 000 001 818 989 403 545 856 475 830 078 125 + 0.000 000 000 000 909 494 701 772 928 237 915 039 062 5 + 0.000 000 000 000 227 373 675 443 232 059 478 759 765 625 + 0.000 000 000 000 028 421 709 430 404 007 434 844 970 703 125 + 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 + 0.000 000 000 000 000 444 089 209 850 062 616 169 452 667 236 328 125 =
0.207 812 496 245 682 876 150 340 234 744 362 533 092 498 779 296 875(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)0 × (1 + 0.207 812 496 245 682 876 150 340 234 744 362 533 092 498 779 296 875) × 2965 =
1.207 812 496 245 682 876 150 340 234 744 362 533 092 498 779 296 875 × 2965 = ...
= 376 656 385 369 825 987 806 345 110 417 022 290 056 255 982 516 643 104 257 383 772 446 260 825 401 480 953 970 347 760 575 068 540 856 031 575 414 412 601 816 309 767 576 438 586 215 795 375 707 528 607 157 212 432 617 130 535 992 226 753 107 116 532 301 436 283 565 427 863 629 360 475 164 332 075 883 534 822 120 045 120 639 556 492 377 708 763 523 628 476 862 201 556 315 838 349 312
0 - 111 1100 0100 - 0011 0101 0011 0011 0011 0011 0010 0011 0001 0011 0100 1000 1110, a 64 bit double precision IEEE 754 binary floating point representation standard to a decimal number, written in base ten (double) = 376 656 385 369 825 987 806 345 110 417 022 290 056 255 982 516 643 104 257 383 772 446 260 825 401 480 953 970 347 760 575 068 540 856 031 575 414 412 601 816 309 767 576 438 586 215 795 375 707 528 607 157 212 432 617 130 535 992 226 753 107 116 532 301 436 283 565 427 863 629 360 475 164 332 075 883 534 822 120 045 120 639 556 492 377 708 763 523 628 476 862 201 556 315 838 349 312(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.