aureooms/js-search

export function interpolate ( delta, a, i, j, k ) {

    var w, d, p;

    w = delta( a[j - 1], a[i] );
    d = delta( k, a[i] );

    if ( w === 0 ) {
        w = 1;
        d = d > 0;
    }

    p = i + Math.floor( d * (j - i - 1) / w );
    return Math.max( i, Math.min( j - 1, p ) );
}