searchengine - concordance and size

import math

# the concordance of a document is a frequency map of the words in the document

class VectorCompare:
    # return the frequency map of words in a document
    def concordance(self, document):
        if type(document) != str:
            raise ValueError('Supplied argument should be of type string')
        con = {}
        for word in document.split(' '):
            if word in con:
                con[word] = con[word] + 1
            else:
                con[word] = 1
        return con

    # calculate the Euclidean norm of the vector (it's length, by the Pythagorean theorem)
    def magnitude(self, concordance):
        if type(concordance) != dict:
            raise ValueError('Supplied argument should be of type dict')
        total = 0
        for word, count in concordance.items():
            total += count ** 2
        return math.sqrt(total)
// ...