I'm trying to create two arrays each with a column from a CSV file. These will get used in Chart.js as data and label arrays.
CSV file contents:
DateTime, Reading
2021-01-05 21:33:05,987
2021-01-05 21:36:36,552
2021-01-05 22:35:08,1035
2021-01-06 14:00:00,111
2021-01-07 17:13:37,101
JavaScript code:
d3.csv("data.csv").then(makeChart);
function makeChart(data)
{
console.log(data);
var DateTimeLabels = data.map(function(d) {return d.DateTime});
var ReadingsData = data.map(function(d) {return d.Reading});
console.log(DateTimeLabels);
console.log(ReadingsData);
...
In the console, the output is as follows:
[{DateTime: "2021-01-05 21:33:05", Reading: "987"}, {DateTime: "2021-01-05 21:36:36", Reading: "552"}, {DateTime: "2021-01-05 22:35:08", Reading: "1035"}, {DateTime: "2021-01-06 14:00:00", Reading: "111"}, {DateTime: "2021-01-07 17:13:37", Reading: "101"}] (5)
["2021-01-05 21:33:05", "2021-01-05 21:36:36", "2021-01-05 22:35:08", "2021-01-06 14:00:00", "2021-01-07 17:13:37"] (5)
[undefined, undefined, undefined, undefined, undefined] (5)
Why does the ReadingsData array come up with undefined values and how can I fix it?
question from:
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