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    <p>The following page may be useful in the case where you need absolute portability of such operations. It discusses software for testing implementations of the IEEE 754 standard, including software for emulating floating point operations. Most information is probably specific to C or C++, however.</p> <p><a href="http://www.math.utah.edu/~beebe/software/ieee/" rel="nofollow noreferrer">http://www.math.utah.edu/~beebe/software/ieee/</a></p> <p><strong>A note on fixed point</strong></p> <p>Binary fixed point numbers can also work well as a substitute for floating point, as is evident from the four basic arithmetic operations:</p> <ul> <li>Addition and subtraction are trivial. They work the same way as integers. Just add or subtract!</li> <li>To multiply two fixed point numbers, multiply the two numbers then shift right the defined number of fractional bits.</li> <li>To divide two fixed point numbers, shift the dividend left the defined number of fractional bits, then divide by the divisor.</li> <li>Chapter four of <a href="http://repository.lib.ncsu.edu/ir/bitstream/1840.16/1599/1/etd.pdf" rel="nofollow noreferrer">this paper</a> has additional guidance on implementing binary fixed point numbers.</li> </ul> <p>Binary fixed point numbers can be implemented on any integer data type such as int, long, and BigInteger, and the non-CLS-compliant types uint and ulong. </p> <p>As suggested in another answer, you can use lookup tables, where each element in the table is a binary fixed point number, to help implement complex functions such as sine, cosine, square root, and so on. If the lookup table is less granular than the fixed point number, it is suggested to round the input by adding one half of the granularity of the lookup table to the input:</p> <pre><code>// Assume each number has a 12 bit fractional part. (1/4096) // Each entry in the lookup table corresponds to a fixed point number // with an 8-bit fractional part (1/256) input+=(1&lt;&lt;3); // Add 2^3 for rounding purposes input&gt;&gt;=4; // Shift right by 4 (to get 8-bit fractional part) // --- clamp or restrict input here -- // Look up value. return lookupTable[input]; </code></pre>
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    1. POIs floating-point math consistent in C#? Can it be?
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    1. USPeter O.
    1. USPeter O.
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    1. COYou should upload this to an open-source code project site, like sourceforge or github. This makes it easier to find, easier to contribute to, easier to put on your resume etc. Also, a few source-code tips (feel free to ignore): Use `const` instead of `static` for constants, so the compiler can optimize them; prefer member functions to static functions (so we can call, ex. `myDouble.LeadingZeros()` instead of `IntDouble.LeadingZeros(myDouble)`); try to avoid single-letter variable names (`MultiplyAnyLength`, for example, has 9, making it very hard to follow)
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      1. USBlueRaja - Danny Pflughoeft
    2. COBe careful using `unchecked` and non-CLS-compliant types like `ulong`, `uint`, etc. for speed purposes - because they are so rarely used, the JIT does not optimize them as aggressively, so using them can actually be *slower* than using normal types like `long` and `int`. Also, C# has [operator overloading](http://msdn.microsoft.com/en-us/library/aa288467%28v=vs.71%29.aspx), which this project would benefit greatly from. Finally, are there any associated unit-tests? Besides those small things, **amazing** job Peter, this is ridiculously impressive!
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    3. COThank you for the comments. I do perform unit tests on the code. They are rather extensive, though, much too extensive to release for now. I even write unit-testing helper routines to make writing multiple tests easier. I don't use overloaded operators for now because I have plans of translating the code to Java when I'm done.
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