Q2: Implement retrieval of documents using an inverted file (inverted index). Build postings from a collection of documents and rank documents matching a user query.

Document Retrieval using an Inverted Index

Solution and implementation for Q2 from Information Retrieval (ir).

2_inverted_index_retrieval.py Download

"""Retrieve documents using a simple inverted index."""

documents = {
    "D1": "Machine Learning is useful",
    "D2": "Machine Learning uses data",
    "D3": "Data Science is useful",
}

inverted_index = {}
for doc_id, text in documents.items():
    for word in text.lower().split():
        inverted_index.setdefault(word, []).append(doc_id)

print("Inverted index:")
print(inverted_index)

query = input("\nEnter a search term: ").lower()
print("Matching documents:", inverted_index.get(query, "No documents found"))

Other Questions in Information Retrieval

See All Available Questions

Q1: Write a program to preprocess a text document by tokenizing it, removing stop words, and stemming the remaining words.
Q3: Construct a simple Bayesian network using medical features and demonstrate heart-disease classification. The answer uses a small example dataset and Naive Bayes conditional probabilities. This educational example is not a medical diagnostic tool.
Q4: Implement e-mail spam filtering using a text classification algorithm and an appropriate labeled dataset. Report precision, recall, F1-score, and a confusion matrix.
Q5: Implement an agglomerative hierarchical clustering algorithm using an appropriate dataset. Visualize the dendrogram and report cluster assignments.
Q6: Implement the PageRank algorithm using Python or Beautiful Soup. Demonstrate the ranking on a directed web graph.
Q7: Build a web crawler to collect product information and links from an e-commerce website. Respect the website's terms, robots.txt, rate limits, and access controls; demonstrate with a site you own or have permission to crawl.

Download