Creating a simple searching program

Question

Decided to delete and ask again, was just easier! Please do not vote down as have taken on board what people have been saying.

I have two nested dictionaries:-

wordFrequency = {'bit':{1:3,2:4,3:19,4:0},'red':{1:0,2:0,3:15,4:0},'dog':{1:3,2:0,3:4,4:5}}

search = {1:{'bit':1},2:{'red':1,'dog':1},3:{'bit':2,'red':3}}

The first dictionary links words a file number and the number of times they appear in that file. The second contains searches linking a word to the number of times it appears in the current search.

I want to extract certain values so that for each search I can calculate the scalar product between the number of times words appear in a file and number of times they appear in a search divided by their magnitudes, then see which file is most similar to the current search i.e. (word 1 appearances in search * word 1 appearances in file) + (word 2 appearances in search * word 2 appearances in file) etc. And then return a dictionary of searches to list of file numbers, most similar first, least similar last.

Expected output is a dictionary:

{1:[4,3,1,2],2:[1,2,4,3]}

etc.

The key is the search number, the value is a list of files most relevant first.

(These may not actually be right.)

This is what I have:-

def retrieve():
    results = {}
    for word in search:
        numberOfAppearances = wordFrequency.get(word).values()
        for appearances in numberOfAppearances:
            results[fileNumber] = numberOfAppearances.dot()
return sorted (results.iteritems(), key=lambda (fileNumber, appearances): appearances, reverse=True)

Sorry no it just says wdir = and then the directory the .py file is in.

• Edit

The entire Retrieve.py file:

from collections import Counter

def retrieve():

    wordFrequency = {'bit':{1:3,2:4,3:19,4:0},'red':{1:0,2:0,3:15,4:0},'dog':    {1:3,2:0,3:4,4:5}}
    search = {1:{'bit':1},2:{'red':1,'dog':1},3:{'bit':2,'red':3}}


    results = {}
    for search_number, words in search.iteritems():
        file_relevancy = Counter()
        for word, num_appearances in words.iteritems():
            for file_id, appear_in_file in wordFrequency.get(word, {}).iteritems():
                file_relevancy[file_id] += num_appearances * appear_in_file

        results[search_number] = [file_id for (file_id, count) in file_relevancy.most_common()]

    return results

I am using the Spyder GUI / IDE for Anaconda Python 2.7, just press the green play button and output is:

wdir='/Users/danny/Desktop'

• Edit 2

In regards to the magnitude, for example, for search number 3 and file 1 it would be:

sqrt (2^2 + 3^2 + 0^2) * sqrt (3^2 + 0^2 + 3^2)

Answer 1

Here is a start:

from collections import Counter
def retrieve():
    results = {}
    for search_number, words in search.iteritems():
        file_relevancy = Counter()
        for word, num_appearances in words.iteritems():
            for file_id, appear_in_file in wordFrequency.get(word, {}).iteritems():
                file_relevancy[file_id] += num_appearances * appear_in_file

        results[search_number] = [file_id for (file_id, count) in file_relevancy.most_common()]

    return results

print retrieve()