1 - 110 0110 1010 - 1000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0100 1100 64 Bit Double Precision IEEE 754 Binary Floating Point Representation Standard Converted to Decimal
1 - 110 0110 1010 - 1000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0100 1100: 64 bit double precision IEEE 754 binary floating point representation standard converted to decimal
What are the steps to convert
1 - 110 0110 1010 - 1000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0100 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.
1
The next 11 bits contain the exponent:
110 0110 1010
The last 52 bits contain the mantissa:
1000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0100 1100
2. Convert the exponent from binary (from base 2) to decimal (in base 10).
The exponent is allways a positive integer.
110 0110 1010(2) =
1 × 210 + 1 × 29 + 0 × 28 + 0 × 27 + 1 × 26 + 1 × 25 + 0 × 24 + 1 × 23 + 0 × 22 + 1 × 21 + 0 × 20 =
1,024 + 512 + 0 + 0 + 64 + 32 + 0 + 8 + 0 + 2 + 0 =
1,024 + 512 + 64 + 32 + 8 + 2 =
1,642(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 = 1,642 - 1023 = 619
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).
1000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0100 1100(2) =
1 × 2-1 + 0 × 2-2 + 0 × 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 + 0 × 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 + 1 × 2-46 + 0 × 2-47 + 0 × 2-48 + 1 × 2-49 + 1 × 2-50 + 0 × 2-51 + 0 × 2-52 =
0.5 + 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 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0.000 000 000 000 014 210 854 715 202 003 717 422 485 351 562 5 + 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 + 0 =
0.5 + 0.000 000 000 000 014 210 854 715 202 003 717 422 485 351 562 5 + 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 =
0.500 000 000 000 016 875 389 974 302 379 414 439 201 354 980 468 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)1 × (1 + 0.500 000 000 000 016 875 389 974 302 379 414 439 201 354 980 468 75) × 2619 =
-1.500 000 000 000 016 875 389 974 302 379 414 439 201 354 980 468 75 × 2619 = ...
= -3 263 311 827 866 253 767 455 298 605 012 641 852 155 983 969 194 654 975 947 016 996 235 766 715 519 964 968 821 266 164 741 601 824 990 438 568 627 989 145 642 641 682 721 221 418 247 179 370 657 924 642 247 975 297 265 279 768 559 048 678 440 960
1 - 110 0110 1010 - 1000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0100 1100, a 64 bit double precision IEEE 754 binary floating point representation standard to a decimal number, written in base ten (double) = -3 263 311 827 866 253 767 455 298 605 012 641 852 155 983 969 194 654 975 947 016 996 235 766 715 519 964 968 821 266 164 741 601 824 990 438 568 627 989 145 642 641 682 721 221 418 247 179 370 657 924 642 247 975 297 265 279 768 559 048 678 440 960(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.