What are the steps to convert
1 - 0111 1101 - 011 1100 1101 1000 0101 0010, a 32 bit single 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 8 bits contain the exponent:
0111 1101
The last 23 bits contain the mantissa:
011 1100 1101 1000 0101 0010
2. Convert the exponent from binary (from base 2) to decimal (in base 10).
The exponent is allways a positive integer.
0111 1101(2) =
0 × 27 + 1 × 26 + 1 × 25 + 1 × 24 + 1 × 23 + 1 × 22 + 0 × 21 + 1 × 20 =
0 + 64 + 32 + 16 + 8 + 4 + 0 + 1 =
64 + 32 + 16 + 8 + 4 + 1 =
125(10)
3. Adjust the exponent.
Subtract the excess bits: 2(8 - 1) - 1 = 127,
that is due to the 8 bit excess/bias notation.
The exponent, adjusted = 125 - 127 = -2
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).
011 1100 1101 1000 0101 0010(2) =
0 × 2-1 + 1 × 2-2 + 1 × 2-3 + 1 × 2-4 + 1 × 2-5 + 0 × 2-6 + 0 × 2-7 + 1 × 2-8 + 1 × 2-9 + 0 × 2-10 + 1 × 2-11 + 1 × 2-12 + 0 × 2-13 + 0 × 2-14 + 0 × 2-15 + 0 × 2-16 + 1 × 2-17 + 0 × 2-18 + 1 × 2-19 + 0 × 2-20 + 0 × 2-21 + 1 × 2-22 + 0 × 2-23 =
0 + 0.25 + 0.125 + 0.062 5 + 0.031 25 + 0 + 0 + 0.003 906 25 + 0.001 953 125 + 0 + 0.000 488 281 25 + 0.000 244 140 625 + 0 + 0 + 0 + 0 + 0.000 007 629 394 531 25 + 0 + 0.000 001 907 348 632 812 5 + 0 + 0 + 0.000 000 238 418 579 101 562 5 + 0 =
0.25 + 0.125 + 0.062 5 + 0.031 25 + 0.003 906 25 + 0.001 953 125 + 0.000 488 281 25 + 0.000 244 140 625 + 0.000 007 629 394 531 25 + 0.000 001 907 348 632 812 5 + 0.000 000 238 418 579 101 562 5 =
0.475 351 572 036 743 164 062 5(10)
= -0.368 837 893 009 185 791 015 625
1 - 0111 1101 - 011 1100 1101 1000 0101 0010, a 32 bit single precision IEEE 754 binary floating point representation standard to a decimal number, written in base ten (float) = -0.368 837 893 009 185 791 015 625(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.