Dimple Time Format Juggling

问题

I am very confused by the way dates are handled by dimple (or maybe it is just D3).

My problem can be divided in two questions:

1. My dates come as a column in my csv file in the format %Y-%m-%d %H:%M:%S. In order to convert them to date objects, I currently use the same loop I used to have in "vanilla" d3.

   data.forEach(function (d) {
      var format = d3.time.format("%Y-%m-%d %H:%M:%S");
      d.Date = format.parse(d.Date);
   });
   

   Is there a quicker way to do this with? Maybe with the timeField function? Or dateParseFormat? I might be wrong but those functions looks like helpers to handle dates.

2. The main reason why I want to control my time objects is to be able to reformat them. Documentation seems to indicate that the tickFormat function can be used for this. Unfortunately I also failed at using it. My best guess:

   var x = myChart.addCategoryAxis("x", "Date");

   x.tickFormat(d3.time.format("%Y-%m")); // For example for a year-month format

only returns

x.tickFormat is not a function

Thanks a lot,

Xavier

回答1:

The time formatting relates to time axes. You don't need your loop if you want to use the time axis, just use:

myChart.addTimeAxis("x", "Date", "%Y-%m-%d %H:%M:%S", "%Y-%m");

where "%Y-%m-%d %H:%M:%S" is your input and "%Y-%m" is your output format. The reason for the "x.tickFormat is not a function" error is that it isn't :). You can set the tickFormat used by the time axis as a property if you wish but it isn't required if you use the factory method above:

myTimeAxis.tickFormat = "%Y-%m";

But this only works with a time axis.

An example of the time axes in action can be found here:

http://dimplejs.org/advanced_examples_viewer.html?id=advanced_time_axis

Hope that helps

John

来源：https://stackoverflow.com/questions/20195870/dimple-time-format-juggling