Searching an element in a list of double-nested dictionaries with generator

Question

I have a list of dictionaris. In every dictionary, i need to use values, which are in the dictionaries, which are in the dictionaries:

[{'Cells': {'Address': 'Нижний Кисельный переулок, дом 3, строение 1',
   'AdmArea': 'Центральный административный округ',
   'District': 'Мещанский район',
   'IsNetObject': 'нет',
   'Name': 'Юнион Джек',
   'OperatingCompany': None,
   'PublicPhone': [{'PublicPhone': '(495) 621-19-63'}],
   'SeatsCount': 30,
   'SocialPrivileges': 'нет',
   'geoData': {'coordinates': [37.62158794615201, 55.76536695660836],
    'type': 'Point'},
   'global_id': 20660594},
  'Id': 'ae3e9479-070f-4d66-9429-de3acd8427ac',
  'Number': 1},
 {'Cells': {'Address': 'проспект Мира, дом 91, корпус 1',
   'AdmArea': 'Северо-Восточный административный округ',
   'District': 'Останкинский район',
   'IsNetObject': 'нет',
   'Name': 'Бар «Джонни Грин Паб»',
   'OperatingCompany': None,
   'PublicPhone': [{'PublicPhone': '(495) 602-45-85'}],
   'SeatsCount': 50,
   'SocialPrivileges': 'нет',
   'geoData': {'coordinates': [37.635709999611, 55.805575000159],
    'type': 'Point'},
   'global_id': 20660628},
  'Id': 'c5301186-00bb-4a1f-af03-6f3237292a51',
  'Number': 2},

I'm given coordinates [lattitude, attitude]. I want to find the smallest distance between given coordinates and coordinates in dictionaries. So i need to iterate over dictionaries and calculate the distance. I'am quite new, but i want to be more proffesional with using a generator to find the distance. But, using __next__(), will stop iterating as soon as it meets the condition, so i'am just dont if it is possible.

So, to be short: What is the most efficient way to find the smallest distance from a given spot in this data structure?

@dsgdfg As you can see, all 'Cells' keys are in diffrent dictionaries. Is it still a problem if i need to iterate over these dicts? Thanks you for your advice about geo metrics, but i think i just need a minimum Euclidian distance — , Sep 24 '16 at 09:46
@jonrsharpe nobody answered it yet. The solution doesnt work — , Sep 24 '16 at 09:51
@dsgdfg My points are very close to each other( territiry of 1 town), so i consider WSG as flat coordinates — , Sep 24 '16 at 09:53
@VladislavLadenkov then downvote the solution and comment explaining the problem with it, but don't start moving the goalposts — jonrsharpe, Sep 24 '16 at 09:55
@dsgdfg Thank you for your solution, but it implies creating a list of all coordinates. I mentioned, that i dont want a memory-massive solution, i want to iterate over dicts in a list, count the distance, and if it is less than the previus minimum, then remeber it, else - forget — , Sep 24 '16 at 09:57

score 0 · Accepted Answer · edited May 23 '17 at 12:01

0

First, let's assume you have a function get_distance() which finds distance between two points with lat and long. I can describe it, but I think for now it is not the point of the question. Then, the code will be look like:

cells = {...} # your data is here
point = [..] # coordinates of the point 
distances = {get_distance(point, cell['Cells']['geoData']['coordinates']): cell['Id'] for cell in cells}  # I don't know do you need a whole entry to be found or only `Id`
closest_id = distances[min(distances.keys())]

Off course it is only of possible solutions. I've made it with dict comprehension but sometimes it is more easy to rea to do it with suaul for loop. Please let me know if something is unclear.

If you also have problems with writing get_distance function - here is an one of examples: How can I quickly estimate the distance between two (latitude, longitude) points? (of course it needs to be modified a bit to look like get_distance function)

edited May 23 '17 at 12:01

Community

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answered Sep 24 '16 at 09:15

Andrii Rusanov

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Please, see Edit1! – Sep 24 '16 at 09:40
can't reproduce it... What version of Python do you use? Maybe you can try to go with something like `dict([(get_distance(point, cell['Cells']['geoData']['coordinates']), cell['Id']) for cell in cells])` – Andrii Rusanov Sep 24 '16 at 09:58
I'am using python 3.5 . Make it clear for me please, `cells` - the list of dictionaries in your solution? – Sep 24 '16 at 10:01
Hm, then it should be fine... Yes, cells is a list of dict with addresses – Andrii Rusanov Sep 24 '16 at 10:33
Above is copy of the code that looks(almost) like yours - I made a typo in variable name, which is doesn't matter although. Code works for me.. – Andrii Rusanov Sep 24 '16 at 10:53
Thanks you, Andrew – Sep 24 '16 at 11:01

Searching an element in a list of double-nested dictionaries with generator

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