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// Evol functions.
// Authors:
// gumi
// Description:
// Randomization helper functions.
// any(<arg>{, ...<arg>})
// returns one argument randomly
function script any {
return getarg(rand(getargcount()));
}
// any_of(<array>)
// returns any member of the array
function script any_of {
return getelementofarray(getarg(0), getarrayindex(getarg(0)) + rand(getarraysize(getarg(0)) - getarrayindex(getarg(0))));
}
// relative_array_random(<array: 0, {[value, probability]..}>)
// returns a random entry from the array, by relative probability
// the first key of the array should be 0 and every entries are a tuple
// of [value, probability]
function script relative_array_random {
.@total_prob = getelementofarray(getarg(0), 0);
.@initial_index = getarrayindex(getarg(0));
.@initial_index = .@initial_index ? .@initial_index : 1;
freeloop(true);
if (.@total_prob < 1 || getarg(1, false))
{
// first calculation, or forced re-calculation
.@total_prob = 0;
.@size = getarraysize(getarg(0));
for (.@i = .@initial_index + 1; .@i < .@size; .@i += 2)
.@total_prob += getelementofarray(getarg(0), .@i);
// we cache on the first key
set(getelementofarray(getarg(0), 0), .@total_prob);
}
.@target_sum = rand(.@total_prob);
for (.@i = .@initial_index; .@sum < .@target_sum; .@i += 2)
.@sum += getelementofarray(getarg(0), .@i + 1);
freeloop(false);
return getelementofarray(getarg(0), max(0, .@i - 2));
}
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