如何从多个数组中复制不重复的元素

Posted 2023-04-12

【中文标题】如何从多个数组中复制不重复的元素

【英文标题】：how to copy non duplicate elements from multiple arrays

【发布时间】：2021-08-21 09:35:03

【问题描述】：

如何从多个动态数组中复制不重复的元素

我想让每个 graphmonthdata 的长度相同。 例如 graphmonthdata[2] 长度为 4，所以我想让它的长度以嵌套数组中的最高长度为准，而另一个嵌套数组中缺少值，反之亦然。 基本上所有嵌套数组都应该具有相同的长度和相同的元素，方法是从另一个嵌套数组中添加缺失的元素

在 javascript 或 c# 中请帮助谢谢！

示例嵌套数组

 graphmonthdata = [
    [
        "Bug Fixing",
        "Deployment",
        "Design",
        "Development",
        "Documentation",
        "Downtime",
        "Learning & Skill Upgrade",
        "Meetings",
        "Project Management",
        "Requirement Understanding",
        "Review",
        "Support",
        "Testing"
    ],
    [
        "Bug Fixing",
        "Deployment",
        "Development",
        "Documentation",
        "Meetings",
        "Review",
        "Support",
        "Testing",
        "UAT/Prod. Fixes"
    ],
    [
        "Meetings",
        "Organisational Activity",
        "Planned/Unplanned Leave",
        "Testing"
    ]
]

最终的数组应该是这样的

 graphmonthdata = 
[
    [
        "Bug Fixing",
        "Deployment",
        "Design",
        "Development",
        "Documentation",
        "Downtime",
        "Learning & Skill Upgrade",
        "Meetings",
        "Organisational Activity",
        "Planned/Unplanned Leave",
        "Project Management",
        "Requirement Understanding",
        "Review",
        "Support",
        "Testing",
        "UAT/Prod. Fixes"
    ],
    [
        "Bug Fixing",
        "Deployment",
        "Design",
        "Development",
        "Documentation",
        "Downtime",
        "Learning & Skill Upgrade",
        "Meetings",
        "Organisational Activity",
        "Planned/Unplanned Leave",
        "Project Management",
        "Requirement Understanding",
        "Review",
        "Support",
        "Testing",
        "UAT/Prod. Fixes"
    ],
    [
        "Bug Fixing",
        "Deployment",
        "Design",
        "Development",
        "Documentation",
        "Downtime",
        "Learning & Skill Upgrade",
        "Meetings",
        "Organisational Activity",
        "Planned/Unplanned Leave",
        "Project Management",
        "Requirement Understanding",
        "Review",
        "Support",
        "Testing",
        "UAT/Prod. Fixes"
    ]
]

【问题讨论】：

使用Set。

如果最大的内部数组不包含 smaller 数组中的项目怎么办。例如。 [['a','b','c'], ['a'], ['b'], ['d']]。在这种情况下应该是什么输出？

@YevgenGorbunkov 它应该填充较小数组中的缺失值，例如这里最长的数组是 graphmonthdata[0] 没有来自 graphmonthdata[2] 的值，即“Planned/Unplanned Leave”所以我们最长的需要加上“Planned/Unplanned Leave”。希望这可以消除您的疑问

如果您需要从所有嵌套数组中获取所有唯一值，只需使用Set 和Array.prototype.flat()：const uniqueValues = [...new Set(graphmonthdata.flat())]

【参考方案1】：

您可以使用Set 创建所有唯一值的列表。然后只需 map 覆盖具有唯一值的现有数组。

const graphmonthdata = [["Bug Fixing","Deployment","Design","Development","Documentation","Downtime","Learning & Skill Upgrade","Meetings","Project Management","Requirement Understanding","Review","Support","Testing"],["Bug Fixing","Deployment","Development","Documentation","Meetings","Review","Support","Testing","UAT/Prod. Fixes"],["Meetings","Organisational Activity","Planned/Unplanned Leave","Testing"]];

const uniqueItems = new Set(graphmonthdata.flat());
const result = graphmonthdata.map(() => [...uniqueItems]);

console.log(result);