Question

So I have a multi-dimensional dictionary that has a numeric key identifying an inner dictionary, but the inner dictionary does not have numeric keys. I’m having difficulty creating a sorted list of keys based on the value of one of the inner dictionary’s string indices. I might not have described the issue properly, so here is an example script highlighting the issue:

#! /usr/bin/python
my_dict = {
        12608: {
                'market_data':  {
                    'sellVolume': 69210, 'buyValue': 296.20999999999998,  
                    'sellValue': 523.20000000000005, 'buyVolume': 9210899
                    }
            },
        24513: {
            'market_data': {
                'sellVolume': 42148, 'buyValue': 548.95000000000005,  
                 'sellValue': 890.0, 'buyVolume': 11213386
                }
            },
        12773:  {
                'market_data': {
                    'sellVolume': 383000, 'buyValue': 609.54999999999995, 
                    'sellValue': 799.98000000000002, 'buyVolume': 10285288
                    }
            },
        24486: {
            'market_data': {
                'sellVolume': 1314250, 'buyValue': 99.780000000000001,  
                'sellValue': 425.0, 'buyVolume': 14690060
                }
            },
        2801: {
            'market_data': {
                'sellVolume': 247577, 'buyValue': 348.98000000000002, 
                'sellValue': 518.94000000000005, 'buyVolume': 10325916
                }
            }
    }

d_sorted = sorted(my_dict, key=lambda \
       x: my_dict[x]['market_data']['buyValue'], reverse=True)

print "key\tbuyValue"
for key in d_sorted:
    print "%d\t%.2f" % (key, my_dict[key]['market_data']['sellValue'])

And here are the results of the script

# Results:
# key         buyValue
# 12773   799.98
# 24513   890.00
# 2801    518.94
# 12608   523.20
# 24486   425.00

# Expected:
# key         buyValue
# 24513   890
# 12773   799.98
# 12608   523.2
# 2801     518.94
# 24486   425

The example dictionary is not my full use-case, but a stripped down version to show the problem (there’s another inner-dictionary that was unimportant to the issue for example). I mention this because there might be a better data type to use than dictionary that I’m unaware of, being new to python.

The question here was instrumental in getting me this far, and the main difference I see is that my second dimension does not use integer keys.

I’m using python version 2.6.7, if it matters.

Answer 1

As I said in the comment below the question, your table header says “BuyValue” and you are printing “Sell value”. Going by the output what you expect, I think you just made a small mistake in setting the sorter function.

It should be:

lambda x: my_dict[x]['market_data']['sellValue']

and not

lambda x: my_dict[x]['market_data']['buyValue']