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Binary floating point and .NETWorked example

Consider the following 64-bit binary number:
0100000001000111001101101101001001001000010101110011000100100011

As a double, this is split into:

Sign: 0
Exponent: 10000000100 binary = 1028 decimal
Mantissa: 0111001101101101001001001000010101110011000100100011
This is therefore a normal number of value
(-1)0 x 1.0111001101101101001001001000010101110011000100100011 (binary) x 21028-1023
which is more simply represented as
1.0111001101101101001001001000010101110011000100100011 (binary) x 25
or
101110.01101101101001001001000010101110011000100100011

In decimal, this is 46.42829231507700882275457843206822872161865234375, but .NET will display it by default as 46.428292315077 or with the "round-trip" format specifier as 46.428292315077009.

обратите внимание на последнюю фразу:
but .NET will display it by default as 46.428292315077 or with the "round-trip" format specifier as 46.428292315077009