dice

Rolls a dice with relative probabilities stored in proportions. Returns the index in proportions that was chosen.

size_t dice(Rng rnd, Num[] proportions)
size_t dice(R rnd, Range proportions)
size_t
dice
(
R
Range
)
(
ref R rnd
,
Range proportions
)
if (
isForwardRange!Range &&
isNumeric!(ElementType!Range)
&&
!isArray!Range
)
size_t dice(Range proportions)
size_t dice(Num[] proportions)

Parameters

rnd R: (optional) random number generator to use; if not specified, defaults to rndGen
proportions Range: forward range or list of individual values whose elements correspond to the probabilities with which to choose the corresponding index value

Return Value

Type: size_t

Random variate drawn from the index values [0, ... proportions.length - 1], with the probability of getting an individual index value i being proportional to proportions[i].

Examples

auto x = dice(0.5, 0.5);   // x is 0 or 1 in equal proportions
auto y = dice(50, 50);     // y is 0 or 1 in equal proportions
auto z = dice(70, 20, 10); // z is 0 70% of the time, 1 20% of the time,
                           // and 2 10% of the time

auto rnd = MinstdRand0(42);
auto z = rnd.dice(70, 20, 10);
assert(z == 0);
z = rnd.dice(30, 20, 40, 10);
assert(z == 2);

dice

Parameters

Return Value

Examples

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