data 1 ーーーー  注意 data直接指定 x,y1,y2の指定の仕方が chart は独特(textareaの縦)
da0[0] =["月","1","2","3","4","5"] → ["1","2","3","4","5"]
da0[1] =["電気量17",1497,1392,1257,1300,901] → [1497,1392,1257,1300,901]
da0[2] =["電気量18",200,,,164,331]  → [200,,,164,331] 

by  https://qiita.com/tabetomo/items/f1fa423bf826a1d2efb8

 Chart.jsを使う 

Ver.3 折れ線



const chart = new Chart(ctx, {
    type: 'line',
    data: [ data 詳細 ], // data 詳細はここの [ ]内に書く
    options: {
        plugins: {
            title: { display: true, text: 'Chart Title' }
        },
        scales: {
            x: { type: 'linear' },  //  (Ver.2) xAxes: → (Ver.3) x:
            y: { type: 'linear'}   //  (Ver.2) yAxes: → (Ver.3) y:
        }
    },
    plugins: [dataLabelPlugin], // plugins はここの [ ]内に書く
})
--------
月,1,2,3,4,5
電気量17,1497,1392,1257,1300,901
電気量18,,-,-,164,331
電気量19,756,704,650,562,459
電気量20,621,574,734,544,513


月,電気量17,電気量18,電気量19
1,1497,555,756
2,1392,444,704
3,1257,333,650
4,1300,164,562
5,901,331,459


月,電気量17,電気量18,電気量19,電気量20
1,1497,90,756,621
2,1392,90,704,574
3,1257,90,650,734
4,1300,164,562,544
5,901,331,459,513
6,704,325,309,351
7,690,274,304,256
8,732,340,349,301
9,751,302,378,330
10,730,267,304,255
11,821,309,387,361
12,1139,458,483,419
ーーーー
const transpose = a => a[0].map((_, c) => a.map(r => r[c]));
const array = [
    [ 1, 2, 3 ],
    [ 4, 5, 6 ],
    [ 7, 8, 9 ]
];
transpose(array);//