instance method
Enumerable#minmax
() -> [ Elem?, Elem? ]
() { (Elem arg0, Elem arg1) -> ::Integer } -> [ Elem?, Elem? ]
minmax → [minimum, maximum]
minmax {|a, b| ... } → [minimum, maximum]
enum.c
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static VALUE
enum_minmax(VALUE obj)
{
VALUE memo;
struct minmax_t *m = NEW_MEMO_FOR(struct minmax_t, memo);
m->min = Qundef;
m->last = Qundef;
if (rb_block_given_p()) {
rb_block_call(obj, id_each, 0, 0, minmax_ii, memo);
if (!UNDEF_P(m->last))
minmax_ii_update(m->last, m->last, m);
}
else {
rb_block_call(obj, id_each, 0, 0, minmax_i, memo);
if (!UNDEF_P(m->last))
minmax_i_update(m->last, m->last, m);
}
if (!UNDEF_P(m->min)) {
return rb_assoc_new(m->min, m->max);
}
return rb_assoc_new(Qnil, Qnil);
}
Returns a 2-element array containing the minimum and maximum elements according to a given criterion. The ordering of equal elements is indeterminate and may be unstable.
With no argument and no block, returns the minimum and maximum elements, using the elements’ own method <=> for comparison:
Example
(1..4).minmax # => [1, 4] (-4..-1).minmax # => [-4, -1] %w[d c b a].minmax # => ["a", "d"] {foo: 0, bar: 1, baz: 2}.minmax # => [[:bar, 1], [:foo, 0]] [].minmax # => [nil, nil]
With a block given, returns the minimum and maximum elements as determined by the block:
Example
%w[xxx x xxxx xx].minmax {|a, b| a.size <=> b.size } # => ["x", "xxxx"] h = {foo: 0, bar: 1, baz: 2} h.minmax {|pair1, pair2| pair1[1] <=> pair2[1] } # => [[:foo, 0], [:baz, 2]] [].minmax {|a, b| a <=> b } # => [nil, nil]