Basic extraction, analysis and visualization of PyconIndia 2012 tweets

pycon.py

#!/usr/bin/env python

import os
import json
import numpy as np
from pandas import DataFrame, concat
from sklearn.feature_extraction.text import TfidfVectorizer
from sklearn.decomposition import PCA
from sklearn.cluster import KMeans
from matplotlib.pyplot import imshow, plot, show, figure, title, yticks


# Download this file from https://gist.github.com/3809261
filename = os.path.join('pyconindia2012.json')
f = open(filename, 'r')

###############################################################################
# Decoding the json file, getting the data in a pandas dataframe and saving it as
# an xls file.
###############################################################################

tweets = []
for line in f:
    tweets.append(json.loads(line))

tweeters = []
texts = []
timestamps = []
metadata = []
for tweet in tweets:
    tweeters.append(tweet['from_user_name'])
    texts.append(tweet['text'])
    timestamps.append(tweet['created_at'])
    metadata.append(tweet['metadata']['result_type'])

tweet_dict = {
    'tweeters':tweeters, 'texts':texts, 'timestamps':timestamps,
    'metadata':metadata
}

df = DataFrame(tweet_dict)
df.to_excel('pycontweets_pandas.xls')



###############################################################################
# Processing the text in tweets to remove redundancies
###############################################################################

# These characters are unwated in the words in a tweet.
unchars = ['@','#','http', 'rt', 'RT', 'and', 'at', 'by', 'for', 'in', 'is',
           'of','on','the', 'two', 'with', 'to', 'was', 'day', 'will', 'it', 'who',
           'had']

proc_text = []

for text in texts:
    words = text.split(' ')
    wordlist = []
    for word in words:
        if np.prod([unchar not in word for unchar in unchars]):
            wordlist.append(word)
    s = ''
    for word in wordlist:
        s += word + ' '
    proc_text.append(s)

df['texts'] = proc_text



###############################################################################
# Tokenizing and analyzing the text in tweets
###############################################################################

vectorizer = TfidfVectorizer()
text_vectorized = vectorizer.fit_transform(proc_text)
tv_sum = np.sum(text_vectorized.toarray(), axis=0)

plot(tv_sum)
show()

thresh = input('Enter Threshold:\n')

inds = tv_sum > thresh

keyword_inds = []
for i in range(len(inds)):
    if inds[i]:
        keyword_inds.append(i)

keywords = []
for key in vectorizer.vocabulary_:
    if vectorizer.vocabulary_[key] in keyword_inds:
        keywords.append(key)

for keyword in keywords:
    if len(keyword)<3:
        keywords.remove(keyword)
        keyword_inds.remove(vectorizer.vocabulary_[keyword])


imshow(text_vectorized.toarray().T, aspect='auto')
yticks(keyword_inds, tuple(keywords), rotation=0)
title('Image Plot of Words in tweets')
show()


# Making a PCA plot:

pca = PCA(2, whiten=True)
pc_red = pca.fit_transform(text_vectorized.toarray())

figure()
plot(pc_red[:,0], pc_red[:,1], 'ro')
title('PCA Plot')
show()

# Performing K-means clustering
k = input('Input cluster numbers:\n')
km = KMeans(2)
km.fit(pc_red)

figure()
plot(km.cluster_centers_[:,0], km.cluster_centers_[:,1], 'r+', markersize=20)
plot(pc_red[:,0], pc_red[:,1], 'bo')
show()

Classy - you have forgotten to close the file handler :-)

Whoa... saw this comment just now, five months later. Don't even remember what I did in that script!