用数组数据循环javascript

Question

I'm new to javascript, and I'm having trouble figuring out how to loop through some code so that it will basically create an array that I can then pass on to my plot variable.

I'm not really sure where to start. Right now I have a chunk of code that takes my first dataset (dataOne) and formats it so that it can go into my plot variable. I basically need to do that three more times for the other data sets - hoping to include the example.getDataSets function to loop through somehow.

Is there a good way to do this?

Here is my code:

script.js

var example = {};

example.data = {
    dataOne: {data: [{"date":1333238400000,"data":23},{"date":1333324800000,"data":37},{"date":1333411200000,"data":49},{"date":1333497600000,"data":54},{"date":1333584000000,"data":30},{"date":1333670400000,"data":19},{"date":1333756800000,"data":15},{"date":1333843200000,"data":19},{"date":1333929600000,"data":145}]},
    dataTwo: {data: [{"date":1335830400000,"data":63},{"date":1335916800000,"data":77},{"date":1336003200000,"data":66}]},
    dataThree: {data: [{"date":1341100800000,"data":24},{"date":1341187200000,"data":50},{"date":1341273600000,"data":43},{"date":1341360000000,"data":39},{"date":1341446400000,"data":56},{"date":1341532800000,"data":66}]},
    dataFour: {data: [{"date":1333238400000,"data":71},{"date":1333324800000,"data":46},{"date":1333411200000,"data":66},{"date":1333497600000,"data":73},{"date":1333584000000,"data":105},{"date":1333670400000,"data":84}]}
}

example.getDataSets = function(){
    return ['dataOne', 'dataTwo', 'dataThree', 'dataFour']
}

example.getSeries = function(month){
    return example.data[month]
}

example.processData = function(data){
    var newData = []
    for(var i = 0; i < data.length; i++){
        newData.push([data[i].date, data[i].data])
    };
    return newData;
}

My script in the HTML page:

$.getScript("script.js")
    .done(function() {

    var b = example.getSeries('dataOne');
    var d = example.processData(b.data);
    // first correct the timestamps - they are recorded as the daily
    // midnights in UTC+0100, but Flot always displays dates in UTC
    // so we have to add one hour to hit the midnights in the plot
    for (var i = 0; i < d.length; ++i)
      d[i][0] += 60 * 60 * 1000;

    var plot = $.plot($("#placeholder"), [d] , options);

Any suggestions are much appreciated!

Answer 1

Loop over the value returned from .getDataSets , too

var sets = example.getDataSets(), set_i = 0, // get list of sets
    b = {}, d = [], i = 0, plot; // set-up vars
for(; set_i < sets.length; set_i++){ // loop over each set
    b = example.getSeries( sets[ set_i ] ); // get your set
    d = example.processData(b.data);
    for (i = 0; i < d.length; ++i)
      d[i][0] += 60 * 60 * 1000;

    plot = $.plot($("#placeholder"), [d] , options);
    // ... etc with plot
}

If you want them all in one array before plotting, use concat on another array (call it d_total or something) and then in the set loop, d_total = d_total.concat( d ); , then plot outside loop

Answer 2

I'm assuming you want to process each of

var b = example.getSeries(X);

where X is, in turn, 'dataOne', 'dataTwo', 'dataThree', 'dataFour'?

If so, you'll be looking for something like this:

// see below for where example.ordering is suggested
for (var i in example.ordered) {
  var month = example.ordered[i];
  var b = example.getSeries(month);
  var d = example.processData(b.data);
  ... further processing with month, b, d.
}

The getDataSets() is fine for yielding your 'months' in what must be proper order for you. My only concern is that you have the list of months in two places. The array you have is necessary for ordering the months, because you cannot extract the 'month names' from example.data and expect them to be in the same order (keys are essentially stored randomly due to hashing).

The qualification would be if your keys are sortable, but the keys you have here are not. Of course, if you're building the pair of structures from the same source, then storing the data in the associated array (example.data object) along with a separate array to indicate ordering is both common and acceptable. Ideally you'd pair these two into yet another object so they can be handled as a team.

Since your array of ordered months is literally 'lost' in a function, I would suggest you add something like

example.ordering = [ ..... ]

and even better, push the months onto the end of that list in the same order they are put into the hash. I would be using a helper function to store the data:

example.ordering = [];  // initially empty
example.storeSet = function (month, dataList) {
    example.ordering.push(month);
    example.data[month] = { data : dataList };
}

....
// now store the data
example.storeSet('dataOne',   [{"date":1333238400000,"data":23}, ....]);
example.storeSet('dataTwo',   [{"date":1335830400000,"data":63}, ....]);
example.storeSet('dataThree', [{"date":1341100800000,"data":24}, ....]);
example.storeSet('dataFour',  [{"date":1333238400000,"data":71}, ....]);

Of course my code is untested (of course!) but it looks right, and I'm sure you can fix any stupid mistakes I might have made.

Answer 3

I am new and understand your frustration when you have sat and looked and still cannot find the answer. However, what I think you are looking for is something like this:

for (example.data=dataOne;example.data<dataFour;example.data=example.data+increment)
{
    code to be executed
}

or maybe even recursively but I am not the best at that but below is an standard example

function recurs(p1) {
    p1--;
    if (p1 < 0) return // exit condition
        setTimeout("recurs("+p1+")",1);
}