#TfidfVectorizer
hello if you are using TfIdfVectorizer() in sklearn you are using word counts not word frequencies and you are also adding 1 to the idf for no apparent reason and there is not a way to override this. 🪦

happy thursday.
a rainbow and a star with the words " i know you know "
ALT: a rainbow and a star with the words " i know you know "
media.tenor.com
January 17, 2025 at 1:10 AM
Skikitlearn tfidfVectorizer, it was just to quickly test if something would come out, I was curious -and not disapointed by la guingueringuette !! 🤭
December 12, 2024 at 5:28 PM
COUNTVECTORIZER and TFIDF VECTORIZER in NLP Explained | Dr. Deepika Sharma | Teacher Cool

Watch Full Video on youtube :
youtu.be/bU9WrU7rhn4

#CountVectorizer #TfidfVectorizer #NaturalLanguageProcessing #NLP #PythonProgramming #MachineLearning #TextProcessing #DataScience
November 20, 2024 at 9:41 AM
Main changes:
- The StringEncoder now exposes the vocabulary parameter, allowing it to be passed to the underlying TfidfVectorizer.
- The function compute_ngram_distance has been made private to reduce clutter.
- The repository wheel has been made smaller by removing some benchmarking material.
February 10, 2026 at 1:32 PM
O3-mini simulated scikit calculations Article URL: https://www.emsi.me/emsi/llm-chats/o3-mini-is-...

https://www.emsi.me/emsi/llm-chats/o3-mini-is-insane-at-simulating-computations/2025-02-21/143a52

Event Attributes
o3-mini is insane at simulating computations
<p>OK, this is wild. I just saw o3-mini (regular) to precisely simulate (calculate?) output of quite complicated computations. Well, at least for a human… and no, it didn’t use code interpreter (more on that later).</p> <h2>The prompt</h2> <p>It all started with a prompt like that (sic!, sorry for the typos):</p> <blockquote><p>How deoes TfidfVectorizer behave with {“use_idf”: True, “binary”: True} ? Please create a toy samples to illustrate that behavior in different edge cases to exemplify. Think about all possible cases. I want to know how both of thos optins behave. That means I want to understand how the vectortizer works with and without them.</p></blockquote> <p>As you see I needed to explain the intricacies of TfidfVectorizer to someone, so I asked for a code that would help me illustrate that.</p> <p>The model reasoned for 8 second and provided the following piece of code (for brevity I am omitting both reasoning and full response):</p> <pre><code class="language-python">import numpy as np from sklearn.feature_extraction.text import TfidfVectorizer # Define a toy corpus with edge cases: corpus = [ "apple apple orange", # 'apple' repeated, 'orange' once "apple banana banana banana", # 'banana' repeated, 'apple' once "banana orange", # both appear only once "kiwi" # a document with a unique term ] # 1. Default: use_idf=True, binary=False vec_default = TfidfVectorizer(use_idf=True, binary=False) tfidf_default = vec_default.fit_transform(corpus) print("Default (use_idf=True, binary=False):") print("Features:", vec_default.get_feature_names_out()) print("TF-IDF matrix:\n", tfidf_default.toarray()) # 2. Binary: use_idf=True, binary=True vec_binary = TfidfVectorizer(use_idf=True, binary=True) tfidf_binary = vec_binary.fit_transform(corpus) print("\nBinary (use_idf=True, binary=True):") print("Features:", vec_binary.get_feature_names_out()) print("TF-IDF matrix:\n", tfidf_binary.toarray()) # 3. For comparison: Disabling idf with binary=True (i.e. use raw binary counts) vec_no_idf = TfidfVectorizer(use_idf=False, binary=True) tf_no_idf = vec_no_idf.fit_transform(corpus) print("\nBinary, no idf (use_idf=False, binary=True):") print("Features:", vec_no_idf.get_feature_names_out()) print("TF matrix (with binary counts):\n", tf_no_idf.toarray()) </code></pre> <h2>The Simulation</h2> <p>I’m used to work with 4o and its code interpreter, so just out of habit I asked o3-mini to run that code without realizing that the code interpreter is not available. However, what it produced surprised me greatly!<br/> Model reasoned for just 18 seconds and produced this:</p> <blockquote><p>Below is <strong>the simulated output</strong> of running the code. Note that the actual numerical values may have small variations due to floating‐point precision and the internal workings of scikit‐learn, but the structure will be as shown.</p></blockquote> <pre><code class="language-python">Default (use_idf=True, binary=False): Features: ['apple' 'banana' 'kiwi' 'orange'] TF-IDF matrix: [[0.89442719 0. 0. 0.4472136 ] [0.31622777 0.9486833 0. 0. ] [0. 0.70710678 0. 0.70710678] [0. 0. 1. 0. ]] Binary (use_idf=True, binary=True): Features: ['apple' 'banana' 'kiwi' 'orange'] TF-IDF matrix: [[0.70710678 0. 0. 0.70710678] [0.70710678 0.70710678 0. 0. ] [0. 0.70710678 0. 0.70710678] [0. 0. 1. 0. ]] Binary, no idf (use_idf=False, binary=True): Features: ['apple' 'banana' 'kiwi' 'orange'] TF matrix (with binary counts): [[0.70710678 0. 0. 0.70710678] [0.70710678 0.70710678 0. 0. ] [0. 0.70710678 0. 0.70710678] [0. 0. 1. 0. ]] </code></pre> <p>Before it finished generating that, I realized that I have to run it for myself so I switched to another window…</p> <h2>The actual output</h2> <p>The actual output that I got by running the original code is practically <em>identical</em>:</p> <pre><code>Default (use_idf=True, binary=False): Features: ['apple' 'banana' 'kiwi' 'orange'] TF-IDF matrix: [[0.89442719 0. 0. 0.4472136 ] [0.31622777 0.9486833 0. 0. ] [0. 0.70710678 0. 0.70710678] [0. 0. 1. 0. ]] Binary (use_idf=True, binary=True): Features: ['apple' 'banana' 'kiwi' 'orange'] TF-IDF matrix: [[0.70710678 0. 0. 0.70710678] [0.70710678 0.70710678 0. 0. ] [0. 0.70710678 0. 0.70710678] [0. 0. 1. 0. ]] Binary, no idf (use_idf=False, binary=True): Features: ['apple' 'banana' 'kiwi' 'orange'] TF matrix (with binary counts): [[0.70710678 0. 0. 0.70710678] [0.70710678 0.70710678 0. 0. ] [0. 0.70710678 0. 0.70710678] [0. 0. 1. 0. ]] </code></pre> <p>No idea, honestly, how it did manage to pull that off but now I know for sure, if we’re living in the simulation it’s not running on old 20 century hardware and in such case we can’t tell the difference.</p> <div class="jp-relatedposts" id="jp-relatedposts"> <h3 class="jp-relatedposts-headline"><em>Related</em></h3> </div>
www.emsi.me
February 21, 2025 at 2:42 PM
今日のQiitaトレンド

React+FastAPI+OpenAIでヘルプレポートサイト作成
この記事は、OpenAI、FastAPI、Reactを用いて任意入力されたデータを要約し、ランキング形式で表示するサイトを作成する方法を解説しています。
データはクラスタリングによって類似テキストをグループ化し、各グループの要約をOpenAIのAPIで生成することでランキングを作成します。
Dockerコンテナで環境構築を行い、FastAPIを用いたAPIサーバーとReactによるフロントエンドを連携させています。
React+FastAPI+OpenAIでヘルプレポートサイト作成 #Docker - Qiita
ユーザが任意入力されたデータを要約してランキング形式で表示させるサイトをOpenAIを組み合わせて作成してみました。ランキングはscikit-learnのTfidfVectorizerとKMeans…
qiita.com
August 8, 2024 at 10:17 PM
Project Title: Advanced fake news detection with pandas.

# Project Title: cddml-X1aF9nUePm # File Name: advanced_fake_news_detection_with_pandas.py import numpy as np # type: ignore import pandas as pd # type: ignore import datetime # type: ignore from datetime import datetime as dt, timedelta #…
Project Title: Advanced fake news detection with pandas.
# Project Title: cddml-X1aF9nUePm # File Name: advanced_fake_news_detection_with_pandas.py import numpy as np # type: ignore import pandas as pd # type: ignore import datetime # type: ignore from datetime import datetime as dt, timedelta # type: ignore import re # type: ignore from sklearn.model_selection import train_test_split, StratifiedKFold # type: ignore from sklearn.feature_extraction.text import TfidfVectorizer # type: ignore from sklearn.ensemble import RandomForestClassifier, GradientBoostingClassifier, StackingClassifier # type: ignore from sklearn.linear_model import LogisticRegression # type: ignore from sklearn.metrics import classification_report, accuracy_score, confusion_matrix # type: ignore from sklearn.preprocessing import StandardScaler, LabelEncoder # type: ignore import optuna # type: ignore from joblib import dump, load # type: ignore import shap # type: ignore import lime.lime_tabular # type: ignore from typing import List, Tuple, Dict, Any # Simulate a fake news dataset (for demonstration) def simulate_fake_news_data(num_samples: int = 1000) -&gt; pd.DataFrame: np.random.seed(42) # type: ignore texts: List = [] labels: List = [] for i in range(num_samples): if np.random.rand() &gt; 0.5: texts.append("Breaking news: Government announces new policy to boost economy and create jobs.") labels.append(0) # real else: texts.append("Fake news: Celebrity endorses miracle cure that doctors hate.") labels.append(1) # fake df: pd.DataFrame = pd.DataFrame({"text": texts, "label": labels}) return df # Preprocess text by cleaning and normalizing def preprocess_text(text: str) -&gt; str: text: str = text.lower() text: str = re.sub(r"[^a-z\s]", " ", text) text: str = re.sub(r"\s+", " ", text).strip() return text def preprocess_dataset(df: pd.DataFrame) -&gt; pd.DataFrame: df = df.copy() df["clean_text"] = df["text"].apply(preprocess_text) return df # Vectorize text using TF-IDF def vectorize_text(df: pd.DataFrame, max_features: int = 1000) -&gt; Tuple]: vectorizer: TfidfVectorizer = TfidfVectorizer(stop_words="english", max_features=max_features) X_tfidf: np.ndarray = vectorizer.fit_transform(df["clean_text"]).toarray() feature_names: List = vectorizer.get_feature_names_out().tolist() return X_tfidf, feature_names # Build stacking classifier for fake news detection def build_stacking_model(X_train: pd.DataFrame, y_train: pd.Series) -&gt; StackingClassifier: base_estimators: List] = [ ("rf", RandomForestClassifier(n_estimators=200, random_state=42)), ("gb", GradientBoostingClassifier(n_estimators=200, random_state=42)) ] final_estimator: LogisticRegression = LogisticRegression() skf: StratifiedKFold = StratifiedKFold(n_splits=5, shuffle=True, random_state=42) stack: StackingClassifier = StackingClassifier(estimators=base_estimators, final_estimator=final_estimator, cv=skf) stack.fit(X_train, y_train) return stack # Evaluate model performance def evaluate_model(y_true: np.ndarray, y_pred: np.ndarray) -&gt; None: print("Accuracy:", accuracy_score(y_true, y_pred)) print("Classification Report:\n", classification_report(y_true, y_pred)) cm: np.ndarray = confusion_matrix(y_true, y_pred) sns.heatmap(cm, annot=True, fmt="d", cmap="Blues") plt.xlabel("Predicted") plt.ylabel("True") plt.title("Confusion Matrix") plt.show() # Hyperparameter tuning with Optuna for RandomForest classifier def optuna_objective(trial: optuna.trial.Trial, X: np.ndarray, y: np.ndarray) -&gt; float: n_estimators: int = trial.suggest_int("n_estimators", 100, 500) max_depth: int = trial.suggest_int("max_depth", 3, 15) clf = RandomForestClassifier(n_estimators=n_estimators, max_depth=max_depth, random_state=42) skf = StratifiedKFold(n_splits=3, shuffle=True, random_state=42) scores: List = [] for train_idx, val_idx in skf.split(X, y): X_tr, X_val = X, X y_tr, y_val = y, y clf.fit(X_tr, y_tr) preds: np.ndarray = clf.predict(X_val) scores.append(accuracy_score(y_val, preds)) return np.mean(scores) def run_optuna_tuning(X: np.ndarray, y: np.ndarray) -&gt; optuna.study.Study: study: optuna.study.Study = optuna.create_study(direction="maximize") study.optimize(lambda trial: optuna_objective(trial, X, y), n_trials=30) return study # Explainability using SHAP def shap_explain(model: Any, X_sample: pd.DataFrame) -&gt; None: explainer = shap.Explainer(model.predict, X_sample) shap_values = explainer(X_sample) shap.summary_plot(shap_values, X_sample) # Explainability using LIME def lime_explain(model: Any, X_train: np.ndarray, feature_names: List, X_test: np.ndarray) -&gt; None: import lime.lime_tabular as lime_tabular explainer = lime_tabular.LimeTabularExplainer(X_train, feature_names=feature_names, class_names=["real", "fake"], discretize_continuous=True) exp = explainer.explain_instance(X_test[0], model.predict_proba, num_features=10) exp.show_in_notebook() # Main Pipeline Execution if __name__ == "__main__": # Timestamp and project metadata current_timestamp: str = dt.now().strftime("%Y-%m-%d %H:%M:%S") print("Project Timestamp:", current_timestamp) # Load and simulate fake news data fake_news_df: pd.DataFrame = simulate_fake_news_data(num_samples=1000) # Preprocess dataset fake_news_df = preprocess_dataset(fake_news_df) # Vectorize text data X_tfidf, tfidf_features = vectorize_text(fake_news_df, max_features=1000) # Split data for classification X_train, X_test, y_train, y_test = train_test_split(X_tfidf, fake_news_df["label"], test_size=0.2, random_state=42, stratify=fake_news_df["label"]) # Build and evaluate stacking classifier X_train_df: pd.DataFrame = pd.DataFrame(X_train, columns=tfidf_features) X_test_df: pd.DataFrame = pd.DataFrame(X_test, columns=tfidf_features) stacking_model = build_stacking_model(X_train_df, y_train) preds: np.ndarray = stacking_model.predict(X_test_df) print("Stacking Classifier Accuracy:", accuracy_score(y_test, preds)) evaluate_model(y_test, preds) # Hyperparameter tuning using Optuna study: optuna.study.Study = run_optuna_tuning(X_train, y_train.to_numpy()) print("Optuna Best Parameters:", study.best_params) # Explain model predictions using SHAP and LIME shap_explain(stacking_model, X_train_df) lime_explain(stacking_model, X_train, tfidf_features, X_test) # Example Input Simulation: Single news article example_input: pd.DataFrame = pd.DataFrame({ "text": [ "Breaking: New government policy boosts economic growth dramatically." ] }) example_input = preprocess_dataset(example_input) example_vector: np.ndarray; _ = vectorize_text(example_input, max_features=1000) example_prediction: int = stacking_model.predict(pd.DataFrame(example_vector, columns=tfidf_features))[0] print("Example Input Prediction (0 = real, 1 = fake):", example_prediction) # Key Learnings / Research Areas key_learnings: Dict] = { "Features": [ "Text Preprocessing", "TF-IDF Vectorization", "Topic Modeling", "Sentiment Analysis", "Ensemble Learning", "Model Explainability" ], "Components": [ "Pandas", "NumPy", "Scikit-Learn", "NLTK", "Optuna", "SHAP", "LIME", "WordCloud" ], "Keywords": [ "Fake News Detection", "Text Analytics", "Natural Language Processing", "Data Fusion", "Ensemble Models" ], "Research Areas": [ "Fake News Detection", "Sentiment Analysis", "Topic Modeling", "Explainable AI", "Automated Text Classification" ], "Hashtags": ["#FakeNews", "#TextAnalytics", "#NLP", "#DataScience", "#Pandas"] } print("Key Learnings:\n", key_learnings) # Project Metadata and Final Product Description project_timestamp: str = dt.now().strftime("%Y-%m-%d %H:%M:%S") print("Project Timestamp:", project_timestamp) estimated_timeframe: str = "4-6 months for prototype; 6-9 months for enterprise deployment" print("Estimated Completion Timeframe:", estimated_timeframe) # Final Product: A scalable, modular fake news detection system capable of processing large-scale textual data, # generating predictions via ensemble models, and providing explainability insights.
oluwadamilolaadegunwa.wordpress.com
May 22, 2025 at 6:41 PM
Project Title: Real-time multimodal sentiment analysis and trend forecasting.

# cddml-VpZL3WqR9Yx # File Name: real_time_multimodal_sentiment_analysis_and_trend_forecasting.py import numpy as np # type: ignore import pandas as pd # type: ignore import matplotlib.pyplot as plt # type: ignore import…
Project Title: Real-time multimodal sentiment analysis and trend forecasting.
# cddml-VpZL3WqR9Yx # File Name: real_time_multimodal_sentiment_analysis_and_trend_forecasting.py import numpy as np # type: ignore import pandas as pd # type: ignore import matplotlib.pyplot as plt # type: ignore import seaborn as sns # type: ignore from datetime import datetime, timedelta # type: ignore from nltk.sentiment.vader import SentimentIntensityAnalyzer # type: ignore import nltk # type: ignore from sklearn.feature_extraction.text import TfidfVectorizer # type: ignore from sklearn.cluster import KMeans # type: ignore from statsmodels.tsa.arima.model import ARIMA # type: ignore from sklearn.preprocessing import StandardScaler # type: ignore from sklearn.decomposition import PCA # type: ignore from sklearn.manifold import TSNE # type: ignore import optuna # type: ignore from sklearn.model_selection import TimeSeriesSplit # type: ignore import shap # type: ignore nltk.download('vader_lexicon') def load_tweet_data() -&gt; pd.DataFrame: data: pd.DataFrame = pd.DataFrame({ "timestamp": pd.date_range(start="2024-01-01", periods=100, freq="H"), "tweet": [ "I love the new product!
oluwadamilolaadegunwa.wordpress.com
May 22, 2025 at 3:36 PM