There are lists in the list, how to loop out each list?

[["", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", ""], ["300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104", "300104"], ["2018-03-30", "2018-03-29", "2018-03-28", "2018-03-23", "2018-03-22", "2018-03-21", "2018-03-20", "2018-03-19", "2018-03-16", "2018-03-14", "2018-03-13", "2018-03-12", "2018-03-09", "2018-03-08", "2018-03-07", "2018-03-06", "2018-03-05", "2018-03-02", "2018-03-01", "2018-02-28", "2018-02-27", "2018-02-26", "2018-02-23", "2018-02-22", "2018-02-14", "2018-02-13", "2018-02-12", "2018-02-09", "2018-02-08", "2018-02-07", "2018-02-06", "2018-02-05", "2018-02-02", "2018-02-01", "2018-01-31", "2018-01-30", "2018-01-29", "2018-01-26", "2018-01-25", "2018-01-24"], ["4.79", "5.11", "5.10", "5.40", "5.57", "5.70", "5.21", "5.34", "5.93", "6.49", "5.75", "5.41", "5.30", "5.32", "5.33", "5.33", "5.28", "5.15", "5.10", "5.27", "5.21", "5.09", "4.98", "4.47", "4.11", "4.47", "4.56", "4.57", "4.34", "4.82", "5.36", "5.95", "6.61", "7.34", "8.15", "9.05", "10.06", "11.18", "12.42", "13.80"], ["4.87", "5.11", "5.34", "5.48", "5.73", "5.88", "5.87", "5.34", "5.93", "6.77", "6.16", "5.65", "5.60", "5.45", "5.40", "5.48", "5.42", "5.70", "5.25", "5.54", "5.49", "5.37", "5.35", "4.86", "4.57", "4.51", "4.69", "4.92", "5.28", "4.82", "5.36", "5.95", "6.61", "7.34", "8.15", "9.05", "10.06", "11.18", "12.42", "13.80"], ["4.72", "4.70", "5.01", "4.99", "5.36", "5.30", "5.21", "5.34", "5.93", "6.36", "5.75", "5.38", "5.30", "5.27", "5.20", "5.32", "5.26", "5.09", "5.06", "5.11", "5.12", "5.02", "4.92", "4.35", "4.01", "4.12", "4.34", "4.57", "4.34", "4.82", "5.36", "5.95", "6.61", "7.34", "8.15", "9.05", "10.06", "11.18", "12.42", "13.80"], ["4.76", "4.78", "5.12", "5.08", "5.54", "5.53", "5.87", "5.34", "5.93", "6.59", "6.16", "5.60", "5.46", "5.35", "5.34", "5.38", "5.33", "5.50", "5.20", "5.22", "5.44", "5.28", "5.29", "4.86", "4.42", "4.16", "4.46", "4.57", "5.08", "4.82", "5.36", "5.95", "6.61", "7.34", "8.15", "9.05", "10.06", "11.18", "12.42", "13.80"], ["-0.02", "-0.34", "0.04", "-0.46", "0.01", "-0.34", "0.53", "-0.59", "-0.66", "0.43", "0.56", "0.14", "0.11", "0.01", "-0.04", "0.05", "-0.17", "0.30", "-0.02", "-0.22", "0.16", "-0.01", "0.43", "0.44", "0.26", "-0.30", "-0.11", "-0.51", "0.26", "-0.54", "-0.59", "-0.66", "-0.73", "-0.81", "-0.90", "-1.01", "-1.12", "-1.24", "-1.38", "-1.53"], ["-0.42", "-6.64", "0.79", "-8.30", "0.18", "-5.79", "9.93", "-9.95", "-10.02", "6.98", "10.00", "2.56", "2.06", "0.19", "-0.74", "0.94", "-3.09", "5.77", "-0.38", "-4.04", "3.03", "-0.19", "8.85", "9.95", "6.25", "-6.73", "-2.41", "-10.04", "5.39", "-10.07", "-9.92", "-9.98", "-9.95", "-9.94", "-9.94", "-10.04", "-10.02", "-9.98", "-10.00", "-9.98"], ["1,585,272", "2,889,496", "2,929,088", "2,663,670", "2,185,353", "3,907,513", "4,916,900", "454,889", "236,857", "3,782,598", "1,637,459", "2,695,850", "2,840,371", "1,568,980", "1,882,589", "1,886,108", "2,526,762", "4,395,146", "2,107,575", "3,583,972", "3,562,522", "3,955,894", "5,791,485", "2,824,080", "2,754,325", "2,821,280", "3,116,808", "5,324,391", "8,783,693", "822,437", "19,604", "17,324", "12,781", "9,753", "12,200", "9,785", "6,456", "10,162", "8,014", "24,286"], ["75,812", "139,091", "151,161", "138,534", "121,514", "221,070", "272,138", "24,291", "14,046", "248,715", "97,801", "148,498", "155,513", "83,928", "99,710", "101,605", "134,681", "238,821", "108,763", "189,997", "190,770", "205,485", "303,106", "129,186", "119,478", "121,624", "140,362", "247,522", "410,987", "39,641", "1,051", "1,031", "845", "716", "994", "886", "649", "1,136", "995", "3,351"], ["3.14", "8.01", "6.50", "8.84", "6.69", "9.88", "12.36", "0.00", "0.00", "6.66", "7.32", "4.95", "5.61", "3.37", "3.72", "3.00", "2.91", "11.73", "3.64", "7.90", "7.01", "6.62", "8.85", "11.54", "13.46", "8.74", "7.66", "6.89", "19.50", "0.00", "0.00", "0.00", "0.00", "0.00", "0.00", "0.00", "0.00", "0.00", "0.00", "0.00"], ["4.02", "7.33", "7.43", "6.76", "5.54", "9.91", "12.47", "1.15", "0.60", "9.60", "4.15", "6.84", "7.21", "3.98", "4.78", "4.78", "6.41", "11.15", "5.35", "9.09", "9.08", "10.09", "14.77", "7.20", "7.02", "7.19", "7.95", "13.58", "22.40", "2.22", "0.05", "0.05", "0.03", "0.03", "0.03", "0.03", "0.02", "0.03", "0.02", "0.07"]]

the data format is as above. The length of each sublist is the same.
want to loop into: 

["A","000002","2018-07-30","9","20","8","8.9","-0.2","-0.2","85555","8.9","-0.2","1.5"]
["A","000002","2018-07-30","9","20","8","8.9","-0.2","-0.2","85555","8.9","-0.2","1.5"]
["A","000002","2018-07-30","9","20","8","8.9","-0.2","-0.2","85555","8.9","-0.2","1.5"]
....
Python
Apr.01,2021

it's not impossible to write a loop, but there are more ingenious ways.
take a closer look and you can see that you want to change the rows of the original data table into columns and columns into rows. Consider matrix transposition
transposition means that rows become columns and columns become rows, such as this: the first row on the left 543 becomes the first column on the right

. 

var a = [['a','b'],['a1','b1']];  //
var b = a.reduce((r,c)=>{
    for(let i = 0; i<c.length; iPP) {
        if(r[i]===undefined) r[i] = [];
        r[i].push(c[i]);
    }
    return r;
},[]);
console.log(b);  // [['a','a1'],['b','b1']]

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MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1b3eaf0-2bc87.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b3eaf0-2bc87.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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