Math in Django to get a total returned

Question

I'm trying to get to a result that tells me something like 10.5 hours worked on a project.

here's what I'm doing in my view:

time = Time.objects.filter(my_company=my_company, project=project)
raw_hours = time.aggregate(Sum('hours'))
raw_minutes = time.aggregate(Sum('minutes'))
adj_minutes = raw_minutes.raw_minutes__sum / 100
hours = adj_minutes + raw_hours.raw_hours__sum
return {'hours': hours}

When I add {{ view.hours }} to my template, I'm not seeing anything in the return. I'm expecting view.hours == 10.5 or something like that depending on the math.

So I have two questions. Am I thinking about this correctly and is there a more efficient way to do this?

Thanks for you help.

So, to clarify, this is a different way of doing get_context_data. So instead of having to write a get_context_data each time you can just write a method that attaches to the view. http://reinout.vanrees.org/weblog/2014/05/19/context.html — Dave Merwin, Mar 29 '15 at 02:15

score 0 · Accepted Answer · answered Mar 29 '15 at 01:28

0

You can get both aggregates by doing:

d = time.aggregate(Sum('hours'), Sum('minutes'))

this should return a dictionary that looks like this:

{'hours__sum' : Decimal('10'), 'minutes__sum' : Decimal('630')}

so to access the values you should deal with it the same way as you deal with any other dictionary.

hours = d['hours__sum']

On the template, you only need to provide the key for the context dictionary, in your case:

{{ hours }}

answered Mar 29 '15 at 01:28

Tomás Mena

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I was making things too complicated and I had the wrong syntax. – Dave Merwin Mar 29 '15 at 02:31

Math in Django to get a total returned

1 Answers1