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POWhat are the first 32 bits of the fractional part of this float?
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copied!<p>I am looking at the following <a href="http://en.wikipedia.org/wiki/SHA-2#SHA-256_.28a_SHA-2_variant.29_pseudocode" rel="noreferrer">SHA256 pseudocode</a> on wikipedia.</p> <p>Specifically, I am looking at the following section.</p> <pre><code>//Initialize variables //(first 32 bits of the fractional parts of the square roots of the first 8 primes 2..19): h0 := 0x6a09e667 </code></pre> <p>I am trying to figure out how h0 was generated. I know from the comment that this should be the fractional part of the square root of 2. I believe I can get the fractional part of the square root of 2 by typing the following. All the following code is from the python repl.</p> <pre><code>>>> math.modf(math.sqrt(2))[0] 0.41421356237309515 </code></pre> <p>At the top of the file it states that the declaration of all constants are Big Endian. I know that my environment is Small Endian because I type.</p> <pre><code>>>> import sys >>> sys.byteorder 'little' </code></pre> <p>So, according to my manual manipulation of the hex value in h0, the Little Endian representation should be 0x67e6096a.</p> <pre><code>>>> int(0x67e6096a) 1743128938 </code></pre> <p>And I am stuck. I have tried various manipulations, but non of them end up with this result. I do not know how to get the first 32 bits of the fractional part of a floating point number. I know that somehow my 0.41421356237309515 (float) result can be transformed into 1743128938 (int), but I really have no idea how. What are the steps necessary to get the first 32 bits of the fractional part of a floating point number? Python answers only please.</p> <p>Thank you.</p>

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