使用Array#index方法通过值查找元素: arr = [1, 2, 3, 4, 5] element = arr.index(3) # element 的值为 2(因为3在数组中的索引为2) 如果元素不存在于数组中,index方法将返回nil。使用Array#find方法查找满足条件的第一个元素: arr = [1, 2, 3, 4, 5] element = arr.find { |e| e > 3 ...
select {|obj| block } ->array#等同find_all 省略了if条件判断,反义词reject Returns an array containing all elements of enum for which the given block return returns a true value. 加!号则是改变自身。 (1..10).find_all{|i|i%3==0}#=> [3, 6, 9] each_slice(n) {...} -> nil It...
// expected output: Array ["exuberant", "destruction", "present"] 7.find()方法 Array.prototype.find() find()方法返回数组中满足提供的测试函数的第一个元素的值。否则返回undefined。 const array1 = [5, 12, 8, 8, 44]; const found = array1.find(element => element > 10); console.log(f...
{ |element| replacement.sample } puts array 在上述示例中,我们定义了一个数组array和一个替换数组replacement。map!方法遍历array中的每个元素,并使用replacement.sample随机选择一个替换值进行替换。最后,我们打印出替换后的数组。 请注意,map!方法会直接修改原始数组,而不是创建一个新的数组。如...
在Ruby 中,可以使用 `last` 方法来获取数组的最后一个元素。例如: ```ruby array = [1, 2, 3, 4, 5] last_element = array.last p...
Sometimes, you want to know if an array contains one or more elements based on a test function.[1,2,3,4].any? { |n| n > 2 } # => trueIf you need to get the first object that matches your criteria, you can use find.[
This is a new C-API set to exchange a raw memory area, such as a numeric array and a bitmap image, between extension libraries. The extension libraries can share also the metadata of the memory area that consists of the shape, the element format, and so on. Using these kinds of metad...
它继承于Drawingelement类 它的创建方法在entities对象提供 edge = entities.add_line pt1, pt2 在Edge类中常用的方法很多: #all_connected ⇒ Array<Sketchup::Entity> 用来检索连接到边的所有实体,包括边本身 2、两条边的公共面 #common_face(edge2) ⇒ Sketchup::Face?
This is a new C-API set to exchange a raw memory area, such as a numeric array and a bitmap image, between extension libraries. The extension libraries can share also the metadata of the memory area that consists of the shape, the element format, and so on. Using these kinds of metad...
For MongoDB, use a single field (of type Array) called coordinates (i.e., field :coordinates, type: Array). (See Advanced Model Configuration for using different attribute names.)3. In your model, tell geocoder where to find the object's address:geocoded_by :address...