获取嵌套字典中值的中位数

Question

I have a nested dictionary with the following structure:

Clusters{Cluster_X :{accession1: 8, accession2: 3, accession3: 7}, Cluster_Y :{accession1: 7.....}} 

The dictionary represents clusters of DNA sequences with accession numbers as the key for the sequences length. Now, for each subdictionary in the dictonary , I want to extract the key which represents the median of the sequence lengths for the respective subdictionary.

Does anybody know how to do that?

Answer 1

It is just a sample to print the medians and corresponding keys for each sub-dictionary. In for loop we construct a list l which consists of pairs of a sequence length and a key. Then l is sorted by the lengths.

Clusters = {"Cluster_X" :{"accession1": 8, "accession2": 3, "accession3": 7}," Cluster_Y" :{"accession1": 7, "accession2": 10}} 

for c in Clusters:
    l = [[m,k] for k, m in Clusters[c].items()]
    l.sort()
    print 'median:', l[len(l)//2][0], ' key:', l[len(l)//2][1]