0 - 011 0101 0111 - 1010 0000 0000 0000 0100 0000 0000 0000 0000 0000 0000 0011 1101 64 Bit Double Precision IEEE 754 Binary Floating Point Representation Standard Converted to Decimal
0 - 011 0101 0111 - 1010 0000 0000 0000 0100 0000 0000 0000 0000 0000 0000 0011 1101: 64 bit double precision IEEE 754 binary floating point representation standard converted to decimal
What are the steps to convert
0 - 011 0101 0111 - 1010 0000 0000 0000 0100 0000 0000 0000 0000 0000 0000 0011 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.
0
The next 11 bits contain the exponent:
011 0101 0111
The last 52 bits contain the mantissa:
1010 0000 0000 0000 0100 0000 0000 0000 0000 0000 0000 0011 1101
2. Convert the exponent from binary (from base 2) to decimal (in base 10).
The exponent is allways a positive integer.
011 0101 0111(2) =
0 × 210 + 1 × 29 + 1 × 28 + 0 × 27 + 1 × 26 + 0 × 25 + 1 × 24 + 0 × 23 + 1 × 22 + 1 × 21 + 1 × 20 =
0 + 512 + 256 + 0 + 64 + 0 + 16 + 0 + 4 + 2 + 1 =
512 + 256 + 64 + 16 + 4 + 2 + 1 =
855(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 = 855 - 1023 = -168
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).
1010 0000 0000 0000 0100 0000 0000 0000 0000 0000 0000 0011 1101(2) =
1 × 2-1 + 0 × 2-2 + 1 × 2-3 + 0 × 2-4 + 0 × 2-5 + 0 × 2-6 + 0 × 2-7 + 0 × 2-8 + 0 × 2-9 + 0 × 2-10 + 0 × 2-11 + 0 × 2-12 + 0 × 2-13 + 0 × 2-14 + 0 × 2-15 + 0 × 2-16 + 0 × 2-17 + 1 × 2-18 + 0 × 2-19 + 0 × 2-20 + 0 × 2-21 + 0 × 2-22 + 0 × 2-23 + 0 × 2-24 + 0 × 2-25 + 0 × 2-26 + 0 × 2-27 + 0 × 2-28 + 0 × 2-29 + 0 × 2-30 + 0 × 2-31 + 0 × 2-32 + 0 × 2-33 + 0 × 2-34 + 0 × 2-35 + 0 × 2-36 + 0 × 2-37 + 0 × 2-38 + 0 × 2-39 + 0 × 2-40 + 0 × 2-41 + 0 × 2-42 + 0 × 2-43 + 0 × 2-44 + 0 × 2-45 + 0 × 2-46 + 1 × 2-47 + 1 × 2-48 + 1 × 2-49 + 1 × 2-50 + 0 × 2-51 + 1 × 2-52 =
0.5 + 0 + 0.125 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0.000 003 814 697 265 625 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0.000 000 000 000 007 105 427 357 601 001 858 711 242 675 781 25 + 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 + 0.000 000 000 000 000 888 178 419 700 125 232 338 905 334 472 656 25 + 0 + 0.000 000 000 000 000 222 044 604 925 031 308 084 726 333 618 164 062 5 =
0.5 + 0.125 + 0.000 003 814 697 265 625 + 0.000 000 000 000 007 105 427 357 601 001 858 711 242 675 781 25 + 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 + 0.000 000 000 000 000 888 178 419 700 125 232 338 905 334 472 656 25 + 0.000 000 000 000 000 222 044 604 925 031 308 084 726 333 618 164 062 5 =
0.625 003 814 697 279 169 720 900 426 909 793 168 306 350 708 007 812 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)0 × (1 + 0.625 003 814 697 279 169 720 900 426 909 793 168 306 350 708 007 812 5) × 2-168 =
1.625 003 814 697 279 169 720 900 426 909 793 168 306 350 708 007 812 5 × 2-168 = ...
= 0.000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 004 343 252 849 688 085 374 524 975 453 188 428 508 166 403 418 201 507 834 380 619 973 670 293 404 707 871 552 005 669 031 151 676 751 177 574 313 802 795 447 405 525 480 506 077 729 003 777 676 552 999 764 680 862 426 757 812 5
0 - 011 0101 0111 - 1010 0000 0000 0000 0100 0000 0000 0000 0000 0000 0000 0011 1101, a 64 bit double precision IEEE 754 binary floating point representation standard to a decimal number, written in base ten (double) = 0.000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 004 343 252 849 688 085 374 524 975 453 188 428 508 166 403 418 201 507 834 380 619 973 670 293 404 707 871 552 005 669 031 151 676 751 177 574 313 802 795 447 405 525 480 506 077 729 003 777 676 552 999 764 680 862 426 757 812 5(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.