Javascript 如何使用RxJS从嵌套类型的对象数组中找到最大值和最小值

考虑到我有这个

type DataTableType = {
  name: string;
  series: {
    name: string;
    value: number;
  }[];
}[];

let datatable: DataTableType = [
    {
      name: 'Row 1',
      series: [
        {
          name:'Series 1',
          value:7110
        },
        {
          name:'Series 2',
          value:8240
        },
        {
          name:'Series 3',
          value:2111
        },
        {
          name:'Series 4',
          value:3120
        }
      ]
    },
    {
      name: 'Row 2',
      series: [
        {
          name:'Series 1',
          value:6500
        },
        {
          name:'Series 2',
          value:9120
        },
        {
          name:'Series 3',
          value:5123
        },
        {
          name:'Series 4',
          value:8200
        }
      ]
    },
    {
      name: 'Row 3',
      series: [
        {
          name:'Series 1',
          value:-6453
        },
        {
          name:'Series 2',
          value:-9000
        },
        {
          name:'Series 3',
          value:5009
        },
        {
          name:'Series 4',
          value:8900
        }
      ]
    },
    {
      name: 'Row 4',
      series: [
        {
          name:'Series 1',
          value:8567
        },
        {
          name:'Series 2',
          value:4332
        },
        {
          name:'Series 3',
          value:-3111
        },
        {
          name:'Series 4',
          value:-3222
        }
      ]
    },
    {
      name: 'Row 5',
      series: [
        {
          name:'Series 1',
          value:8333
        },
        {
          name:'Series 2',
          value:3234
        },
        {
          name:'Series 3',
          value:-7323
        },
        {
          name:'Series 4',
          value:1544
        }
      ]
    },
    {
      name: 'Row 6',
      series: [
        {
          name:'Series 1',
          value:2112
        },
        {
          name:'Series 2',
          value:3232
        },
        {
          name:'Series 3',
          value:-8231
        },
        {
          name:'Series 4',
          value:1111
        }
      ]
    },
    {
      name: 'Row 7',
      series: [
        {
          name:'Series 1',
          value:-2112
        },
        {
          name:'Series 2',
          value:3232
        },
        {
          name:'Series 3',
          value:8231
        },
        {
          name:'Series 4',
          value:-9111
        }
      ]
    },
    {
      name: 'Row 8',
      series: [
        {
          name:'Series 1',
          value:-2112
        },
        {
          name:'Series 2',
          value:100
        },
        {
          name:'Series 3',
          value:-3
        },
        {
          name:'Series 4',
          value:0
        }
      ]
    }
  ]

我想使用RxJS从数据表中找到最大值和最小值，我已经完成了下面的操作以找到最大值和最小值

function findMax(column: DataTableType) {
  let maxN = column[0].series[0].value;
  of(...column)
    .pipe(
      mergeMap(
        (item: DataTableType[number], i: number) => from(
          [...item.series]
        )
        .pipe(
          max((a, b) => a.value < b.value? b.value : a.value)
        )
      )
    )
    .subscribe(
      (category: { value: number; }) => {
        maxN = category.value;
      }
    )
  ;
  return maxN;
}

function findMin(column: DataTableType) {
  let minN = column[0].series[0].value;
  of(...column)
    .pipe(
      mergeMap(
        (item: DataTableType[number], i: number) => from(
          [...item.series]
        )
        .pipe(
          min((a, b) => a.value > b.value? b.value : a.value)
        )
      )
    )
    .subscribe(
      (category: { value: number; }) => {
        minN = category.value;
      }
    )
  ;
  return minN;
}

但是每当我运行函数findMax(DataTable)和findMin(DataTable)时，我得到对象数组的最后一个元素(即第8行)的max=0和min=-2112.

我的预期答案应该是max=9120和min=-9111

求求你我需要帮助.