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POGenerate a random number in a Gaussian Range?
 

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  1. POGenerate a random number in a Gaussian Range?
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    <p>I want to use a random number generator that creates random numbers in a gaussian range where I can define the median by myself. I already asked a similar question here and now I'm using this code:</p> <pre><code>class RandomGaussian { private static Random random = new Random(); private static bool haveNextNextGaussian; private static double nextNextGaussian; public static double gaussianInRange(double from, double mean, double to) { if (!(from &lt; mean &amp;&amp; mean &lt; to)) throw new ArgumentOutOfRangeException(); int p = Convert.ToInt32(random.NextDouble() * 100); double retval; if (p &lt; (mean * Math.Abs(from - to))) { double interval1 = (NextGaussian() * (mean - from)); retval = from + (float)(interval1); } else { double interval2 = (NextGaussian() * (to - mean)); retval = mean + (float)(interval2); } while (retval &lt; from || retval &gt; to) { if (retval &lt; from) retval = (from - retval) + from; if (retval &gt; to) retval = to - (retval - to); } return retval; } private static double NextGaussian() { if (haveNextNextGaussian) { haveNextNextGaussian = false; return nextNextGaussian; } else { double v1, v2, s; do { v1 = 2 * random.NextDouble() - 1; v2 = 2 * random.NextDouble() - 1; s = v1 * v1 + v2 * v2; } while (s &gt;= 1 || s == 0); double multiplier = Math.Sqrt(-2 * Math.Log(s) / s); nextNextGaussian = v2 * multiplier; haveNextNextGaussian = true; return v1 * multiplier; } } } </code></pre> <p>Then to verify the results I plotted them with gaussianInRange(0, 0.5, 1) for n=100000000 <img src="https://i.stack.imgur.com/1G8xa.jpg" alt="enter image description here"></p> <p>As one can see the median is really at 0.5 but there isn't really a curve visible. So what I'm doing wrong?</p> <h2>EDIT</h2> <p>What i want is something like this where I can set the highest probability by myself by passing a value.</p> <p><img src="https://i.stack.imgur.com/I0kTP.gif" alt="enter image description here"></p>
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    1. COYou say median, but the code says mean. You say Gaussian (which can take any real value), but then you constrain to a finite range. I think before I could help with the code, I'd need to know what the specification is.
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      1. USDavid Heffernan
    2. COhttp://www.taygeta.com/random/gaussian.html
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      1. USMitch Wheat
    3. COhttp://www.bearcave.com/misl/misl_tech/wavelets/hurst/random.html
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