interval
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Vocabulary
math.intervals

Class description
An interval represents a set of real numbers between two endpoints; the endpoints can either be included or excluded from the interval.

The from and to slots store endpoints, represented as arrays of the shape { number included? }.

Intervals are created by calling [a,b], (a,b), [a,b), (a,b] or [a,a].

Definition

IN: math.intervals

TUPLE: interval { from read-only } { to read-only } ;

Methods

USING: kernel math.intervals math.intervals.private sequences ;

M: interval interval-bounds interval>points [ first ] bi@ ;


USING: accessors combinators.short-circuit kernel math
math.intervals sequences ;

M: interval interval-contains?
    {
        [ from>> first2 [ >= ] [ > ] if ]
        [ to>> first2 [ <= ] [ < ] if ]
    } 2&& ;


USING: kernel math math.intervals sequences ;

M: interval interval-length
    interval>points [ first ] bi@ swap - ;


USING: accessors kernel layouts math math.intervals math.order
sequences ;

M: interval interval-log2
    to>> first 1 max dup most-positive-fixnum >
    [ drop full-interval interval-log2 ]
    [ 1 + >integer log2 [0,b] ] if ;


USING: kernel math math.intervals sequences ;

M: interval interval-singleton?
    interval>points 2dup [ second ] both?
    [ [ first ] bi@ number= ] [ 2drop f ] if ;


USING: accessors db.queries kernel math.intervals nmake ;

M: interval where
    [
        [ from>> "from" where-interval ]
        [ nip infinite-interval? [ " and " 0% ] unless ]
        [ to>> "to" where-interval ] 2tri
    ] in-parens ;