Support for datetime objects in xAxis

[sebasmagri]

Hi.

I've read that support for datetime objects is going to be a feature of the next release. Right now it's kinda critical for me. What's your advance on it? Should I try to do it?

[pgollakota]

@sebasmagri I really haven't gotten a chance to work on this as att as much as I wanted to. You are welcome to to submit a pull request. That would actually be great!

[sebasmagri]

@pgollakota I haven't looked at this, but I'm willing to do it soon as it would make things a lot easier to me. Any hints about the path I should follow?

[pgollakota]

@sebasmagri I am currently at the PyCon. After the PyCon, I'll create a how-to guide for developers explaining how the whole library works. I was really busy with a bunch of transitions personally and professionally and wasn't able to give as much attention to this library as I wanted to. If you are here in California, we could even meet!

[sebasmagri]

@pgollakota I wish I were there :(. Ok no problem, I'll wait then.

[camilonova]

@pgollakota did you have any work on this, i would like to help adding this support, but first i want to make sure you don't have anything yet.

[pgollakota]

@camilonova I don't have anything yet. Please submit a patch and I'll be glad to review it. Thanks a lot!

[rohit-nsit08]

hello , I wanted to use django chartit for my charts but cannot use it because of missing support of datetime objects in x axis ...since this seems to be an open issue .. I wanted to know if someone has done some work on it and I'm ready to use it even if it is not production ready

awaiting reply thanx

[bastir85]

Hey, I added a simple hack to allow lambda functions to postprocess the data obtained from the model. Sebastian

[gabro]

Hi bastir, can you provide an example on how to use your hack?

[bastir85]

Take a look at my pull request.

[gabro]

Thanks, I did take a look but I'm still pretty rusty with this library. I'm working with a DateField and I'd like to use it on the X axis. How can this be achieved with your hack?

[rauch]

See an example https://gist.github.com/3175635 Sure, it's supposed that you've already patched your django-chartit with bastrir85`s hack.

2012/7/25 Gabro < reply@reply.github.com

Thanks, I did take a look but I'm still pretty rusty with this library. I'm working with a DateField and I'd like to use it on the X axis. How can this be achieved with your hack?

---

Reply to this email directly or view it on GitHub: https://github.com/pgollakota/django-chartit/issues/2#issuecomment-7246485

All the best Alexander

[gabro]

Thank you very much :)

[atodorov]

+1 on this issue. I tried another approach to workaround but it didn't work. See issue #8.

[rossiwa]

I'm trying the lambda function work around suggested by bastir85, but am getting the following: "APIinputError: month is not one of the keys of the datasource series. Allowed values are: houston_temp, boston_temp". What am I missing?

[grvhi]

@rossiwa I'm getting the same error and also hoping there's a way around this! In my case, we have a datetimefield in the model which we'd like to use on the x-axis....

[bastir85]

@rossiwa @Erve1879 Can you give a little bit more context? It has been a while since I wrote this code. Did you tried my example?

[grvhi]

@bastir85 - Thanks. I'm just starting out with django_chartit, so I may have missed something. Here's my code:

Models.py:

class TotalRatingCount(models.Model):
    timestamp = models.DateTimeField(default=datetime.now(), null=False,
        blank=False,
        help_text='Datetime of this update.')
    rating_count = models.IntegerField(null=False, blank=False,
        help_text='The amount of ratings.')

Views.py:

def ratingCountGraphs(theRequest):
    """
    Returns a highcharts graph of the saved ratingCounts for the user.
    """
    #Step 1: Create a DataPool with the data we want to retrieve.
    ratingsData=\
        DataPool(
           series=
            [{'options': {
               'source': TotalRatingCount.objects.all()},
              'terms': [
                'timestamp',
                'rating_count']}
             ])

    #Step 2: Create the Chart object
    cht = Chart(
            datasource=ratingsData,
            series_options=
              [{'options':{
                  'type': 'line',
                  'stacking': False},
                'terms':{
                  'timestamp': [
                    'rating_count']
                  }}],
            chart_options=
              {'title': {
                   'text': 'Total Ratings Counts'},
               'xAxis': {
                    'title': {
                       'text': 'Total Ratings'}}})

    #Step 3: Send the chart object to the template.
    return render_to_response('website/rating-counts-graphs.html',
                                {'ratingsChart': cht})

With this code, I get the following error from Django:

datetime.datetime(2013, 5, 23, 7, 30, 2, 165034) is not JSON serializable

I've tried the fix suggested above, but I get the same error as @rossiwa (i.e. 'timestamp is not one of the keys....').

I would love it if you could suggest a fix for this - django_chartit is exactly what I need, but this issue will be a big problem!

Thanks very much

[bastir85]

Yes, this does not work. This is why I did the pull request in the first place. Did you applied it and looked at the example of rauch https://gist.github.com/rauch/3175635 or my reference code: https://github.com/pgollakota/django-chartit/pull/4

[grvhi]

@bastir85 - I did try it, but my mistake was not realising that your pull request hadn't been merged..... Will use your fork and try again. Thanks!

[grvhi]

@bastir85 - OK, using your fork and with the code below, I get no errors, but I'm doing something wrong somewhere....

@staff_member_required
def ratingCountGraphs(theRequest):
    """
    Returns a highcharts graph of the saved ratingCounts for the user.
    """
    #Step 1: Create a DataPool with the data we want to retrieve.
    ratingsData=\
        DataPool(
           series=
            [{'options': {
               'source': TotalRatingCount.objects.all()},
              'terms': [
                ('timestamp', lambda d: time.mktime(d.timetuple())),
                'rating_count']}
             ])

    #Step 2: Create the Chart object
    cht = Chart(
            datasource=ratingsData,
            series_options=
              [{'options':{
                  'type': 'line',
                  'stacking': False},
                'terms':{
                  'timestamp': [
                    'rating_count']
                  }}],
            chart_options=
              {'title': {
                   'text': 'Total Ratings Counts'},
               'xAxis': {
                    'title': {
                       'text': 'Date/Time'}}},
            x_sortf_mapf_mts=(None, lambda i: datetime.fromtimestamp(i).strftime("%D:%M"), False)))

    #Step 3: Send the chart object to the template.
    return render_to_response('website/rating-counts-graphs.html',
                                {'ratingsChart': cht})

[bastir85]

How many datapoints do you have? Did you checked the JS code? maybe it is just a formating issue. It looks a little bit like overlapping text.

[grvhi]

Thanks for your help @bastir85 - got everything working now.

[rossiwa]

I also did not realize that the datetime fix was only in the fork by bastir85. Once I got the updated code, things started working. Thanks!

[rossiwa]

@erve1879, how did you implement the “step” setting? I can’t seem to get any of the Highcharts options to work from within Chartit.

From: Erve1879 [mailto:notifications@github.com] Sent: Tuesday, May 28, 2013 7:08 AM To: pgollakota/django-chartit Cc: rossiwa Subject: Re: [django-chartit] Support for datetime objects in xAxis (#2)

Yes - I've solved the overlapping text issue by using the Highcharts 'step' setting, but my data points and the line are not appearing for some reason.... Instead I get those small blue rectangles visible on the xaxis above the overlapping text. I get no JS errors and the highcharts js is included, so not sure what the issue is.

— Reply to this email directly or view it on GitHub https://github.com/pgollakota/django-chartit/issues/2#issuecomment-18552614 .Image removed by sender.

[grvhi]

@rossiwa Here's my code:

@staff_member_required
def ratingCountGraphs(theRequest):
    """
    Returns a highcharts graph of the saved ratingCounts for the user.
    """
    #Step 1: Create a DataPool with the data we want to retrieve.
    ratingsData=\
        DataPool(
           series=
            [{'options': {
               'source': TotalRatingCount.objects.all()},
              'terms': [
                ('timestamp', lambda d: time.mktime(d.timetuple())),
                'rating_count']}
             ])

    #Step 2: Create the Chart object
    cht = Chart(
            datasource=ratingsData,
            series_options=
              [{'options':{
                  'type': 'line',
                  'stacking': False},
                'terms':{
                  'timestamp': [
                    'rating_count']
                  }}],
            chart_options=
               {'chart':
                    {
                    'zoomType': 'x'
                    },
                'title':
                    {
                    'text': 'Total Ratings Counts'
                    },
                'xAxis':
                    {
                    'labels':
                        {'step': 5, 'rotation': 90, 'align': 'bottom'},
                    'minRange': 10
                    },
                'credits':
                    {
                    'enabled': False
                    }
               },
            x_sortf_mapf_mts=(None, lambda i: datetime.fromtimestamp(i).strftime("%d %b %k:%M"), False))

    #Step 3: Send the chart object to the template.
    return render_to_response('website/rating-counts-graphs.html',
                                {'ratingsChart': cht})

Hope that helps!

[OmenWild]

Found another way to do this based on this snippet http://djangosnippets.org/snippets/1435/ . Add code like the following near the top of chartit/templatetags/chartit.py:

# From http://djangosnippets.org/snippets/1435/
import datetime
from dateutil import tz

def encode_datetime(obj):
    if isinstance(obj, datetime.datetime):
        return obj.astimezone(tz.tzutc()).strftime('%Y-%m-%dT%H:%M:%SZ')
    elif isinstance(obj, datetime.date):
        return obj.strftime('%Y-%m-%dT00:00:00Z')

    raise TypeError(repr(obj) + " is not JSON serializable")

I'm having issues getting Highcharts to properly deal with the datetime even when I add

                'xAxis': {
                   'type': 'datetime',
                    'dateTimeLabelFormats': {
                        'day': '%b %e'
                    },
                }

to chart_options, but I can't tell if that's an issue with the datetime object getting serialized or if I've mis-configured Highcharts.

EDIT: Never mind. The datatime/JSON part works, it just doesn't get passed to Highcharts in a way it can understand.

[kadubarral]

The solution of @bastir85 doesn't work for PivotTables. Anyone have some idea what I can do?

[proprioceptor]

How to get datetime fields from related models?

My Models are

class TrackerRecord(models.Model):
    doctor = models.ForeignKey(User, related_name='tracker_record')
    creation_time = models.DateTimeField(default=timezone.now)
    ....

class TrackerRecordField(models.Model):
    field_value = models.CharField(max_length=200)
    tracker_record = models.ForeignKey(TrackerRecord, related_name='tracker_record_field',null=True,blank=True)
    ....

I want to plot 'field_value' against the 'creation_time' on a line chart.

My View has

DataPool(
     series=
         [{'options': {
                        'source': TrackerRecordField.objects.all()},
                        'terms': [
                                    ('tracker_record__creation_time', lambda d: time.mktime(d.timetuple())),
                                    'field_value',
                                 ]
                      }
         ]

cht = Chart(
        datasource = weatherdata,
        series_options =
          [{'options':{
              'type': 'line',
              'stacking': False},
            'terms':{
              'tracker_record__creation_time': [
                'field_value',]
              }}],
        chart_options =
          {"title":{"text":"Test"},
                "xAxis":{"title":{"text":"Date"}},
                "yAxis":{"title":{"text":"Trackerfield"}}})

        x_sortf_mapf_mts=(None, lambda i: datetime.fromtimestamp(i).strftime("%D:%M"), False))

but the things are not working as my datetime field is in related models. Does Chartit support to access datetime fields accross models. If yes. then please guide.

[atodorov]

Hello everyone, please check out the last 2 commits on master. I've added 4 examples using DateField and DateTimeField on the x axis from the model we're plotting and also from a related model. All of them seem to work without any extra changes.

Since this issue has been open for so long and it looks like it has been fixed I will close it at the end of the week if I don't get any complaints or examples which aren't working .

[atodorov]

closing due to inactivity and my previous comment.