Apply function to each element of an array

Question

I have data in the form

var JSONData = [
        {"id": "Line1", "x_data": ["2005-01-01 01:00", "2005-01-01 02:00", "2005-01-01 03:00", "2005-01-01 04:00", "2005-01-01 05:00"], "y_data": [1, 2, 3, 4, 5]},
        {"id": "Line2", "x_data": ["2005-01-01 01:00", "2005-01-01 02:00", "2005-01-01 03:00", "2005-01-01 04:00", "2005-01-01 05:00"], "y_data": [6, 7, 8, 9, 10]},
        {"id": "Line3", "x_data": ["2005-01-01 01:00", "2005-01-01 02:00", "2005-01-01 03:00", "2005-01-01 04:00", "2005-01-01 05:00"], "y_data": [11, 12, 13, 1, 15]}
    ]

and would like to zip x data with y data and apply a date parsing function to each x element of the returned array of array.

I tried the following but it is returning undefined array.

var parseDate = d3.time.format("%Y-%m-%d %H:%M").parse;
    var nested = d3.nest()
            .key(function(d) {
                return d.name;
            })
            .map(JSONData)
    console.log("nested ", nested);
    var keyring = d3.keys(nested).filter(function(key) {
        return (key !== "x_data" && key !== "y_data");
    });
    console.log("keyring ", keyring);
    var transpose = keyring.map(function(name) {
            console.log("name ", name);
            return {
                name: name,
                values: nested[name].map(function(d) {
                    var zip_data = d3.zip(d.x_data, d.y_data).forEach(function(d, i) {
                        d[0] = parseDate(d[0]);
                        d[1] = +d[1];
                    });
                    console.log("zip data ", zip_data);
                    return zip_data;
                })
            };
        });

Thanks for help.

Answer 1

Try this.

var parseDate = d3.time.format("%Y-%m-%d %H:%M").parse;
var requiredArray= JSONData.map(function(d) { 
               var parsedX = d.x_data.map(function(date){ return parseDate(date) });
               return d3.zip(parsedX , d.y_data) 
            });