0 - 011 0101 0111 - 1010 0000 0000 0000 0100 0000 0000 0000 0000 0000 0000 0011 1100 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 1100: 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 1100, 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 1100
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 1100(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 + 0 × 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 =
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 =
0.625 003 814 697 278 947 676 295 501 878 485 083 580 017 089 843 75(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 + 0.625 003 814 697 278 947 676 295 501 878 485 083 580 017 089 843 75) × 2-168 =
1.625 003 814 697 278 947 676 295 501 878 485 083 580 017 089 843 75 × 2-168 = ...
= 0.000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 004 343 252 849 688 084 781 051 991 343 201 006 791 088 761 570 579 185 695 570 255 372 423 733 012 221 622 125 192 654 615 850 979 311 607 641 078 089 445 441 591 298 418 745 892 284 675 846 894 970 163 702 964 782 714 843 75
0 - 011 0101 0111 - 1010 0000 0000 0000 0100 0000 0000 0000 0000 0000 0000 0011 1100, a 64 bit double precision IEEE 754 binary floating point representation standard to a decimal number, written in base ten (double) = 0.000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 004 343 252 849 688 084 781 051 991 343 201 006 791 088 761 570 579 185 695 570 255 372 423 733 012 221 622 125 192 654 615 850 979 311 607 641 078 089 445 441 591 298 418 745 892 284 675 846 894 970 163 702 964 782 714 843 75(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.