1 - 011 1000 0001 - 1110 0000 1001 0100 0000 0000 0000 0000 0000 0100 0000 0010 0001 64 Bit Double Precision IEEE 754 Binary Floating Point Representation Standard Converted to Decimal
1 - 011 1000 0001 - 1110 0000 1001 0100 0000 0000 0000 0000 0000 0100 0000 0010 0001: 64 bit double precision IEEE 754 binary floating point representation standard converted to decimal
What are the steps to convert
1 - 011 1000 0001 - 1110 0000 1001 0100 0000 0000 0000 0000 0000 0100 0000 0010 0001, 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:
011 1000 0001
The last 52 bits contain the mantissa:
1110 0000 1001 0100 0000 0000 0000 0000 0000 0100 0000 0010 0001
2. Convert the exponent from binary (from base 2) to decimal (in base 10).
The exponent is allways a positive integer.
011 1000 0001(2) =
0 × 210 + 1 × 29 + 1 × 28 + 1 × 27 + 0 × 26 + 0 × 25 + 0 × 24 + 0 × 23 + 0 × 22 + 0 × 21 + 1 × 20 =
0 + 512 + 256 + 128 + 0 + 0 + 0 + 0 + 0 + 0 + 1 =
512 + 256 + 128 + 1 =
897(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 = 897 - 1023 = -126
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).
1110 0000 1001 0100 0000 0000 0000 0000 0000 0100 0000 0010 0001(2) =
1 × 2-1 + 1 × 2-2 + 1 × 2-3 + 0 × 2-4 + 0 × 2-5 + 0 × 2-6 + 0 × 2-7 + 0 × 2-8 + 1 × 2-9 + 0 × 2-10 + 0 × 2-11 + 1 × 2-12 + 0 × 2-13 + 1 × 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 + 1 × 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 + 0 × 2-48 + 0 × 2-49 + 0 × 2-50 + 0 × 2-51 + 1 × 2-52 =
0.5 + 0.25 + 0.125 + 0 + 0 + 0 + 0 + 0 + 0.001 953 125 + 0 + 0 + 0.000 244 140 625 + 0 + 0.000 061 035 156 25 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0.000 000 000 003 637 978 807 091 712 951 660 156 25 + 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 + 0 + 0 + 0 + 0.000 000 000 000 000 222 044 604 925 031 308 084 726 333 618 164 062 5 =
0.5 + 0.25 + 0.125 + 0.001 953 125 + 0.000 244 140 625 + 0.000 061 035 156 25 + 0.000 000 000 003 637 978 807 091 712 951 660 156 25 + 0.000 000 000 000 007 105 427 357 601 001 858 711 242 675 781 25 + 0.000 000 000 000 000 222 044 604 925 031 308 084 726 333 618 164 062 5 =
0.877 258 300 784 895 306 279 054 238 984 826 952 219 009 399 414 062 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)1 × (1 + 0.877 258 300 784 895 306 279 054 238 984 826 952 219 009 399 414 062 5) × 2-126 =
-1.877 258 300 784 895 306 279 054 238 984 826 952 219 009 399 414 062 5 × 2-126 = ...
= -0.000 000 000 000 000 000 000 000 000 000 000 000 022 067 065 276 068 910 478 385 841 917 004 951 789 647 618 368 192 328 148 519 147 683 816 153 230 922 314 012 803 982 521 397 259 345 535 823 982 231 704 576 406 627 893 447 875 976 562 5
1 - 011 1000 0001 - 1110 0000 1001 0100 0000 0000 0000 0000 0000 0100 0000 0010 0001, a 64 bit double precision IEEE 754 binary floating point representation standard to a decimal number, written in base ten (double) = -0.000 000 000 000 000 000 000 000 000 000 000 000 022 067 065 276 068 910 478 385 841 917 004 951 789 647 618 368 192 328 148 519 147 683 816 153 230 922 314 012 803 982 521 397 259 345 535 823 982 231 704 576 406 627 893 447 875 976 562 5(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.