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Function `std.random.choice`

Returns a random, uniformly chosen, element e from the supplied Range range. If no random number generator is passed, the default rndGen is used.


						
				ref auto choice(Range, RandomGen)
				(
				

				  Range range,
				

				  ref RandomGen urng
				

				)
				

				if (isRandomAccessRange!Range && hasLength!Range && isUniformRNG!RandomGen);
				

				

				ref auto choice(Range)
				(
				

				  Range range
				

				);
				

				

				ref auto choice(Range, RandomGen)
				(
				

				  ref Range range,
				

				  ref RandomGen urng
				

				)
				

				if (isRandomAccessRange!Range && hasLength!Range && isUniformRNG!RandomGen);
				

				

				ref auto choice(Range)
				(
				

				  ref Range range
				

				);

Parameters

Name	Description
range	a random access range that has the `length` property defined
urng	(optional) random number generator to use; if not specified, defaults to `rndGen`

Returns

A single random element drawn from the range. If it can, it will return a ref to the range element, otherwise it will return a copy.

Example

auto rnd = MinstdRand0(42);

auto elem  = [1, 2, 3, 4, 5].choice(rnd);
version (D_LP64) // https://issues.dlang.org/show_bug.cgi?id=15147
writeln(elem); // 3

Authors

Andrei Alexandrescu Masahiro Nakagawa (Xorshift random generator) Joseph Rushton Wakeling (Algorithm D for random sampling) Ilya Yaroshenko (Mersenne Twister implementation, adapted from mir-random)

License

Boost License 1.0.