def add_doc(self, doc_id = '', doc_class='', doc_terms=[], do_padding = False):
my_doc_terms = SuperList()
for term in doc_terms:
self.terms.unique_append(term)
my_doc_terms.insert_after_padding(self.terms.index(term))
self.matrix.append({'id': doc_id, 'class': doc_class, 'terms': my_doc_terms})
if do_padding:
self.do_padding()
def add_query(self, query_id = '', query_class='n/a', query_terms=[]):
my_query_terms = SuperList()
my_query_terms.do_padding(new_len=len(self.terms), padding_data=0)
new_terms_count = 0
for term in query_terms:
try:
my_query_terms.insert_after_padding(self.terms.index(term))
except:
# Term not obtaied in traing phase
new_terms_count += 1
self.queries.append({'id': query_id, 'class': query_class, 'terms': my_query_terms, 'new_terms_count': new_terms_count})
def add_query(self, query_id = '', query_class='n/a', query_terms=[]):
my_query_terms = SuperList()
my_query_terms.do_padding(new_len=len(self.terms), padding_data=0)
for term in query_terms:
try:
my_query_terms.insert_after_padding(self.terms.index(term))
except:
# Term not obtaied in traing phase, ignore it
pass
# Calling add_vectors to convert my_query_terms to log_tf values
self.add_vectors(a=my_query_terms, log_tf_a = True)
self.queries.append({'id': query_id, 'class': query_class, 'terms': my_query_terms})
def add_vectors(self, a=[], b=[], log_tf_a = True, log_tf_b = True): if not b: b = SuperList() b.do_padding(new_len=a.__len__(), padding_data=0) elif a.__len__() != b.__len__(): if self.verbose: print "add_vectors:", a.__len__(), "!=", b.__len__() raise Exception sum_vector = SuperList() for i in range(0,a.__len__()): sum_vector.append(self.log_tf(a[i], do_nothing = not log_tf_a) + self.log_tf(b[i], do_nothing = not log_tf_b)) return sum_vector
def compare_queries(self, testing=True):
return_value = []
queries_count = 0
if self.verbose:
print "\nCalculating for %d queries" % len(self.queries)
# Before doing any comparisons we need to convert the matrix to log_tf
# Moved the below line to calculate_training_data()
#self.matrix_to_log_tf()
for query in self.queries:
if self.verbose:
queries_count += 1
if queries_count % (len(self.queries)/5) == 0:
print "- %d querues has been processed" % queries_count
top_k_classes = SuperList()
for doc in self.matrix:
q_distance = self.calculate_vectors_distance(query['terms'], doc['terms'])
item = {"class": doc['class'], "distance": q_distance}
top_k_classes.populate_in_reverse_order(item, self._greater_than)
if self.distance_metric == "euclid":
top_k_classes.reverse()
return_value.append((query["class"], self.get_top_class(nearest_docs=top_k_classes, query_class=query["class"])[0]))
return return_value
def __init__(self, verbose=False, fold="n/a", config=object, ev=object): self.verbose = verbose self.fold = fold self.config = config self.config_data = config.get_configuration() self.distance_metric = self.config_data['distance_metric'] # Set k=0 now, let kNN reset it later on self.k = 0 # confugure the evaluation module self.ev = ev self.terms = SuperList() self.matrix = [] self.queries = [] if self.verbose: print "\nInitialization for fold %s done!" % fold
class Index:
'''
Index is our main class, will inherit others for each IR algorithms from it.
Its two main data-structures are:
* terms: This is a simple list of all terms in all training documents
* matrix: This is our vector space, where terms, documents & classes are mapped to each other
matrix = [{'id': 'document1',
'class': 'spam',
'terms': [1,0,1,0,0,1]
}]
* queries: should look exactly like matrix
queries = [{'id': 'query1',
'class': 'spam', # In testing: This is the known class, else "n/a".
'terms': [1,0,1,1,0,1]
}]
'''
# The initialization functions, we set verbose=True for debugging
def __init__(self, verbose=False, fold="n/a", config=object, ev=object):
self.verbose = verbose
self.fold = fold
self.config = config
self.config_data = config.get_configuration()
self.distance_metric = self.config_data['distance_metric']
# Set k=0 now, let kNN reset it later on
self.k = 0
# confugure the evaluation module
self.ev = ev
self.terms = SuperList()
self.matrix = []
self.queries = []
if self.verbose:
print "\nInitialization for fold %s done!" % fold
# Index[key] returns a list of occurences of term (key) in all documents
def __getitem__(self, key):
try:
index = self.terms.index(key)
return [doc['terms'][index] for doc in self.matrix]
except:
if self.verbose: print sys.exc_info()
raise KeyError
# Gives some stats about the our training-set
def diagnose(self):
print "Diagnose:", self.__class__
print "- Number of Documents:", len(self.matrix)
print "- Number of Terms:", len(self.terms)
#for doc in self.matrix:
# print doc['id'], sum(doc['terms'])
#print "-- Terms:", self.terms
# To align the length of all rows in matrix after new docs/terms are added to it
def do_padding(self):
for doc in self.matrix:
doc['terms'].do_padding(new_len=len(self.terms), padding_data=0)
for query in self.queries:
query['terms'].do_padding(new_len=len(self.terms), padding_data=0)
# We better keep matrix without log_tf at first, in case we need to do Feature Selection
# In case of Rocchio we do the log_tf on the fly when calculating the proto_classes
# Whereas in kNN we might need to call this function
def matrix_to_log_tf(self):
for doc in self.matrix:
doc['terms'] = self.vector_log_tf(doc['terms'])
# To be used for debugging reasons, displays index and matrix
def display_idx(self):
print self.terms
for doc in self.matrix:
print doc['id'], doc['class'], doc['terms']
# Coverts a scalar value to its log_tf (1 + log_10(value) OR zero)
def log_tf(self, value, do_nothing=False):
val = float(value)
if not do_nothing:
val = 1 + math.log10(val) if val != 0 else float(0)
return val
# Coverts a vector value to its log_tf (1 + log_10(value) OR zero)
def vector_log_tf(self, a=[], do_nothing=False):
new_vector = SuperList()
for i in range(0,a.__len__()):
new_vector.append(self.log_tf(value=a[i], do_nothing=do_nothing))
return new_vector
# Divides each item in a vector (list) by a scalar number
def divide_vector(self, vector=[], scalar=1):
result = SuperList()
for item in vector:
result.append(float(item)/scalar)
return result
# Add to vectors (lists) to each other and return the resulting vector
# For each one of them, we can either convert its items into log_tf before addition or not
def add_vectors(self, a=[], b=[], log_tf_a = True, log_tf_b = True):
if not b:
b = SuperList()
b.do_padding(new_len=a.__len__(), padding_data=0)
elif a.__len__() != b.__len__():
if self.verbose: print "add_vectors:", a.__len__(), "!=", b.__len__()
raise Exception
sum_vector = SuperList()
for i in range(0,a.__len__()):
sum_vector.append(self.log_tf(a[i], do_nothing = not log_tf_a) + self.log_tf(b[i], do_nothing = not log_tf_b))
return sum_vector
# Calculates the cosine of the angles between two vectors (lists)
def cos_vectors(self, a=[], b=[]):
if a.__len__() != b.__len__():
if self.verbose: print "cos_vectors:", a.__len__(), "!=", b.__len__()
raise Exception
norm_a_sqrd = norm_b_sqrd = 0
numerator = 0
for i in range(0,a.__len__()):
numerator = numerator + a[i]*b[i]
# Do not use math.pow(), time consuming!
norm_a_sqrd = norm_a_sqrd + (a[i]*a[i])
norm_b_sqrd = norm_b_sqrd + (b[i]*b[i])
# In some cases, when one vector is all zeros, division by zero happens
# Normally this happens when training on small training-set
# And all vocabulary in query is first time to be seen.
try:
return_value = numerator / (math.sqrt(norm_a_sqrd) * math.sqrt(norm_b_sqrd))
except:
return_value = 0
return return_value
# Calculate Euclidean distance between two vectors (lists)
def euclid_vectors(self, a=[], b=[]):
if a.__len__() != b.__len__():
if self.verbose: print "euclid_vectors:", a.__len__(), "!=", b.__len__()
raise Exception
euclid_sqrd = 0
for i in range(0,a.__len__()):
euclid_sqrd += math.pow((a[i] - b[i]), 2)
return math.sqrt(euclid_sqrd)
# Calculate distance between two vectors (lists)
def calculate_vectors_distance(self, a=[], b=[]):
if self.distance_metric == "cos":
return self.cos_vectors(a, b)
elif self.distance_metric == "euclid":
return self.euclid_vectors(a, b)
# We call this each time we are training on a new document
# It is given the document's doc_class and a list of the parsed doc_terms from it
# Since each time we get a new documet, we also might get new terms in our terms and matrix list
# So, if do_padding=True: We extend and pad all old rows in matrix to match the new length of terms now
# Otherwise, we might be postponing this padding process after we finish adding all docs for processing reasons
def add_doc(self, doc_id = '', doc_class='', doc_terms=[], do_padding = False):
my_doc_terms = SuperList()
for term in doc_terms:
self.terms.unique_append(term)
my_doc_terms.insert_after_padding(self.terms.index(term))
self.matrix.append({'id': doc_id, 'class': doc_class, 'terms': my_doc_terms})
if do_padding:
self.do_padding()
# We call this each time we are training on a new query
# It is given the document's query_class and a list of the parsed query_terms from it
# No padding here, since terms in query not learnt during training will be ignored
def add_query(self, query_id = '', query_class='n/a', query_terms=[]):
my_query_terms = SuperList()
my_query_terms.do_padding(new_len=len(self.terms), padding_data=0)
for term in query_terms:
try:
my_query_terms.insert_after_padding(self.terms.index(term))
except:
# Term not obtaied in traing phase, ignore it
pass
# Calling add_vectors to convert my_query_terms to log_tf values
self.add_vectors(a=my_query_terms, log_tf_a = True)
self.queries.append({'id': query_id, 'class': query_class, 'terms': my_query_terms})
# This is where each classifier may do any calculations after loading traing data
# We will leave it for each child class to overwrite it on its own way, or ignore it
# We may add the Feature Selection here, for example: Maximum Information Gain
# Hence, make sure all child classes call their parent's method before overwriting
def calculate_training_data(self):
pass
def _non_zero_indices(self, l): ret = SuperList() for i in range(0,len(l)): if l[i] != 0: ret.append(i) return ret
def divide_vector(self, vector=[], scalar=1): result = SuperList() for item in vector: result.append(float(item)/scalar) return result
def vector_log_tf(self, a=[], do_nothing=False): new_vector = SuperList() for i in range(0,a.__len__()): new_vector.append(self.log_tf(value=a[i], do_nothing=do_nothing)) return new_vector
