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Function `std.mathspecial.normalDistribution`

Standard normal distribution function.


						
				real normalDistribution
				(
				

				  real x
				

				) pure nothrow @nogc @safe;

The normal (or Gaussian, or bell-shaped) distribution is defined as:

normalDist(x) = 1/√(2π) ∫_-∞^x exp( - t²/2) dt = 0.5 + 0.5 * erf(x/sqrt(2)) = 0.5 * erfc(- x/sqrt(2))

To maintain accuracy at values of x near 1.0, use normalDistribution(x) = 1.0 - normalDistribution(-x).

References

http://www.netlib.org/cephes/ldoubdoc.html, G. Marsaglia, "Evaluating the Normal Distribution", Journal of Statistical Software 11, (July 2004).

Authors

Stephen L. Moshier (original C code). Conversion to D by Don Clugston

License

Boost License 1.0.