变换JavaScript二维数组

Question

我正在创建一个仪表板来显示来自各种统计数据的数据。我使用Django和Google Charts来创建图形。到目前为止一切都很好，但我被困在了一个特殊的案例中。

模型类是-

class Registration(models.Model):
    event_type = models.CharField(max_length=80)
    date_time = models.DateField()
    count = models.IntegerField()

我的问题是-

Registration.objects.filter(event_type__in=['VHRAssmntCompleted', 
    'VNAAssmntCompleted', 
    'NonsmokersDeclrtn',
    'MWBAssmntCompleted',
    'VHCAssmntCompleted',
    'SV Document Uploads',
    'PapSmear',
    'Mammogram',], 
    date_time__range=(d3,d1)).order_by('date_time')

我得到的数据格式如下：

[["VHR", "2019-02-1", 23],
["VNA", "2019-02-1", 34],
["PAP", "2019-02-1", 50],
["VHR", "2019-02-2", 92],
["VNA", "2019-02-2", 13],
["PAP", "2019-02-2", 65],
["VHR", "2019-02-3", 192],
["VNA", "2019-02-3", 43],
["PAP", "2019-02-3", 11]]

要创建一个Combo Chart，需要的数据格式如下(类似python dataframe)：

[["date", "VHR", "VNA", "PAP" ],
["2019-02-1", 23,34,50],
["2019-02-2", 92,13,65],
["2019-02-3", 192,43,11]]

我找不到这样做的方法，既可以使用Django ORM查询本身进行格式化，也可以使用JS进行转换。

我需要帮助，知道我应该走哪种方法。

Answer 1

您可以将对象作为值的列位置，并按日期和列收集数据。

​

var data = [["VHR", "2019-02-1", 23], ["VNA", "2019-02-1", 34], ["PAP", "2019-02-1", 50], ["VHR", "2019-02-2", 92], ["VNA", "2019-02-2", 13], ["PAP", "2019-02-2", 65], ["VHR", "2019-02-3", 192], ["VNA", "2019-02-3", 43], ["PAP", "2019-02-3", 11]],
    cols = { VHR: 1, VNA: 2, PAP: 3 },
    result = data.reduce((r, [key, date, value]) => {
        var row = r.find(([d]) => d === date);
        if (!row) {
            r.push(row = [date, 0, 0, 0]);
        }
        row[cols[key]] = value;
        return r;    
    }, [["date", "VHR", "VNA", "PAP"]]);

console.log(result);

.as-console-wrapper { max-height: 100% !important; top: 0; }

​

Answer 2

您可以按日期对它们进行分组，然后使用Object.entries循环遍历分组的结果并将其转换为[date, "VHR", "VNA", "PAP"]

​

const data = [
  ["VHR", "2019-02-1", 23],
  ["VNA", "2019-02-1", 34],
  ["PAP", "2019-02-1", 50],
  ["VHR", "2019-02-2", 92],
  ["VNA", "2019-02-2", 13],
  ["PAP", "2019-02-2", 65],
  ["VHR", "2019-02-3", 192],
  ["VNA", "2019-02-3", 43],
  ["PAP", "2019-02-3", 11]
];

const grouped = data.reduce((all, [key, date, value]) => {

  all[date] = {
    ...all[date],
    [key]: value
  };

  return all;
}, {});

const result = ["date", "VHR", "VNA", "PAP"].concat(
  Object.entries(grouped).map(([date, obj]) => [date, ...Object.values(obj)])
);

console.log(result);

​