Blog Topic

Python for Data Analysis

Python is where analysts go after SQL — to clean messy columns, reshape a frame, join datasets that do not live in the same database, and build a reproducible step between the raw extract and the dashboard. Pandas is the core library for that work, and these tutorials treat it as an analyst tool, not a software engineering exercise. Each guide is built around the API you will actually type in a notebook.

What you will learn

  • Select, filter and reshape a DataFrame without chained-indexing bugs
  • Group and aggregate with groupby().agg() and pivot_table()
  • Merge frames with the correct how and on, and verify the row count afterwards
  • Replace row-by-row loops with vectorised column operations
  • Clean nulls, duplicates and inconsistent strings before analysis

46 articles in this topic

Tutorial

How to Compare Two Columns in Excel: 5 Methods (with Formulas)

How to compare two columns in Excel: equality checks, IF flags, COUNTIF matching, conditional formatting highlights, and VLOOKUP reconciliation steps.

7 min readRead
Interview Prep

Data Analyst Interview Questions 2026: Complete Preparation Guide

30+ data analyst interview questions with answers — SQL, Python, statistics, business cases, and behavioral. A complete guide to ace your next interview.

14 min readRead
Interview Prep

Top 20 Data Scientist Interview Questions and Answers (2026)

Master data scientist interview questions across machine learning, statistics, SQL, Python coding, and product case studies with detailed answers.

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Tutorial

How to Delete Blank Rows in Excel: 4 Safe Methods (with Checks)

How to delete blank rows in Excel safely: Go To Special Blanks, AutoFilter blanks, helper COUNTBLANK flags, and backup checks every analyst must run first.

7 min readRead
Tutorial

Data Cleaning in Excel: How to Remove Blank Rows, Spaces & Duplicates

Master data cleaning in Excel: learn how to remove blank rows in excel, strip stray spaces with TRIM, fix casing, and delete duplicates safely.

6 min readRead
Tutorial

Excel Formulas: The Complete Guide for Data Analysts (2026)

Master essential excel formulas in this complete guide: lookup, math, dynamic arrays, text, financial modeling, and 30+ core functions for analysts.

16 min readRead
Tutorial

Pivot Table in Excel: The Step-by-Step Data Summarization Guide

Master how to create a pivot table in excel: step-by-step tutorial on Rows, Columns, Values, Filters, Calculated Fields, and fast data summarization.

5 min readRead
Interview Prep

Top 20 FastAPI Interview Questions and Answers (2026 Guide)

Master top fastapi interview questions: async/await, Pydantic validation, Depends injection, ASGI vs WSGI, CORS, and deployment architectures.

11 min readRead
Interview Prep

Top 20 Gen AI Interview Questions and Answers (2026 Guide)

Master top gen ai interview questions: Transformers, self-attention, RAG pipelines, fine-tuning vs prompting, LoRA, RLHF, and hallucination fixes.

13 min readRead
Tutorial

How to Combine Two Columns in Excel: Ampersand, TEXTJOIN, and Flash Fill

Learn how to combine two columns in excel using the ampersand (&), TEXTJOIN, CONCAT, and Flash Fill. Add spaces, format dates, and preserve data.

9 min readRead
Tutorial

How to Remove Duplicates in Excel: Built-in Tools, UNIQUE, and Fixes

Learn how to remove duplicates in excel using the Data tab tool, UNIQUE formula, and Advanced Filter. Step-by-step methods, edge cases, and analyst fixes.

9 min readRead
Interview Prep

Top 20 Machine Learning Interview Questions and Answers (2026 Guide)

Master the top 20 machine learning interview questions: bias-variance tradeoff, regularization, ROC-AUC, XGBoost, and production model evaluation.

12 min readRead
Tutorial

How to Merge Two Cells in Excel: Merge vs CONCAT vs TEXTJOIN

How to merge two cells in Excel: Merge & Center, the & operator, CONCAT and TEXTJOIN. Keep values safe, fix sorting issues, and choose the right method.

7 min readRead
Interview Prep

Top 20 Pandas Interview Questions and Coding Answers (2026 Guide)

Master Pandas interview questions with practical DataFrame coding solutions, loc vs iloc, groupby aggregations, merging, and memory optimization.

11 min readRead
Interview Prep

Top 20 Python Basic Interview Questions and Answers (2026 Guide)

Master the top 20 python basic interview questions: list vs tuple, mutable vs immutable, decorators, generators, and core coding questions with answers.

10 min readRead
Tutorial

Python for Data Analysis: The Complete Workflow Playbook (2026)

Master python data analysis with this complete playbook: pandas wrangling, exploratory data analysis, statistical cohorts, and production data pipelines.

16 min readRead
Tutorial

Python Tutorial: The Complete Guide for Data Analysts (2026)

Master Python programming with this comprehensive python tutorial for data analysts: variables, data structures, control flow, functions, NumPy, Pandas, and real-world projects.

16 min readRead
Tutorial

A/B Testing in Python: Sample Size, Hypothesis Testing & P-Value Analysis

Complete A/B testing guide for data analysts in Python. Calculate sample sizes with statsmodels, detect Sample Ratio Mismatch (SRM), run proportion z-tests and Welch's t-tests, and avoid the peeking problem.

14 min readRead
Tutorial

Customer Analytics in Python: Cohort Analysis, RFM Segmentation & LTV

Master customer analytics in Python with Pandas and Seaborn. Calculate RFM scores, build customer segments, run monthly cohort retention heatmaps, and estimate Customer Lifetime Value (LTV).

13 min readRead
Tutorial

How to Filter & Sort in Excel Without Mixing Data (Safe Guide)

Learn how to filter and sort in Excel without mixing up data or breaking rows. Fix filters stopping at blank rows and avoid the selection trap with Ctrl+T.

5 min readRead
Tutorial

Market Basket Analysis in Python: Support, Confidence, Lift & Apriori Explained

Master Market Basket Analysis and Association Rule Mining in Python. Learn the mathematical intuition behind Support, Confidence, and Lift, one-hot encode transaction baskets, and implement Apriori and FP-Growth using Pandas and Mlxtend.

12 min readRead
Tutorial

REST APIs for Data Analysts in Python: Authentication, Pagination & JSON Normalization

Master REST API data extraction in Python. Learn how to handle Bearer tokens and API keys, loop through offset and cursor pagination, flatten nested JSON with pd.json_normalize(), and build fault-tolerant pipelines with automatic retries.

12 min readRead
Tutorial

Python Exploratory Data Analysis (EDA): The Complete Step-by-Step Workflow

Master the complete 6-stage Python Exploratory Data Analysis (EDA) framework. Learn structured data inspection, missing value imputation, IQR outlier detection, distribution analysis, correlation heatmaps, and feature profiling.

13 min readRead
Tutorial

Python Pandas for Data Analysis: Getting Started Guide (2026)

Learn Python Pandas for data analysis from scratch. DataFrames, filtering, groupby, merging, data cleaning, and 5 one-liners every data analyst should know.

10 min readRead
Tutorial

Product Analytics in Python: Funnel Conversion, Drop-off & User Journey Mapping

Master product funnel analysis in Python with Pandas and Plotly. Calculate step-by-step conversion rates, drop-off percentages, time-to-convert distributions, and interactive Sankey user journeys.

11 min readRead
Tutorial

Time Series Analysis & Forecasting in Python: Trend, Seasonality & Moving Averages

Complete guide to time series analysis and forecasting in Python. Master datetime indexing, resampling, moving average smoothing, seasonal decomposition, and the Augmented Dickey-Fuller (ADF) stationarity test.

12 min readRead
Interview Prep

A/B Testing in Python: From Sample Size to p-Value Without the Ritual

Run A/B tests in Python the right way — simulate control vs variant, check SRM, run chi-square and t-tests, and read p-values correctly.

6 min readRead
Tutorial

API Masterclass in Python: Authentication, Pagination, and JSON to DataFrame

Call any REST API from Python — handle API keys, Basic Auth, query params, pagination, and flatten nested JSON into Pandas DataFrames.

5 min readRead
Tutorial

Applied ML Cheatsheet in Python: Iris Dataset From EDA to Cross-Validation

End-to-end ML in Python on the Iris dataset — EDA, train-test split, scaling, logistic regression, decision trees, and metrics.

4 min readRead
Tutorial

Customer Analytics in Python: Cohort, RFM, and the First Query That Matters

Run RFM segmentation and cohort retention in Python — recency, frequency, monetary scores and a retention heatmap from transaction logs.

5 min readRead
Tutorial

Python Database Connectivity: SQLite to BigQuery Without Hardcoding Passwords

Connect Python to SQLite, PostgreSQL, MySQL, Snowflake and BigQuery with SQLAlchemy and pandas read_sql — securely via .env files.

4 min readRead
Tutorial

EDA in Python: A Checklist That Catches Silent Data Errors

A step-by-step EDA checklist in Python — data loading, missing values, outliers, and feature engineering — with a downloadable Jupyter notebook.

6 min readRead
Tutorial

Python Lists and Dictionaries: 10 Assignments With Answers in Python

Master Python lists and dicts — creating, slicing, appending, merging, and iterating — with 10 graded assignments and solutions.

4 min readRead
Tutorial

Market Basket Analysis in Python: Support, Confidence, and What to Do With Them

Build a market basket analysis in Python — basket matrix, co-occurrence, lift scores, and a rule-based recommender from transaction logs.

6 min readRead
Tutorial

NumPy Foundations: 30 Questions That Build Array Intuition

Learn NumPy from zero — arrays vs lists, zeros, arange, reshape, broadcasting, and vectorised operations with 30 hands-on questions.

4 min readRead
Tutorial

Pandas Advanced Masterclass: Merge, Rank, and Window Functions Like SQL

Advanced Pandas — set_index, merge joins, rank vs dense_rank, shift/lead-lag, and groupby window functions mirroring SQL.

4 min readRead
Tutorial

Pandas Cheatsheet: The 7 Sections Every Analyst Memorises

The Pandas cheatsheet analysts actually use — inspect, select, filter, handle nulls, sort, groupby, and merge with one-liner patterns.

4 min readRead
Tutorial

Pandas Fundamentals: 40 Questions to Go From List to DataFrame

Pandas fundamentals in 40 questions — Series, DataFrame, head, dtypes, loc vs iloc, filtering, sorting, and null handling.

4 min readRead
Tutorial

Pandas Master Workbook: 50 GroupBy, Aggregate, and Merge Drills

50 Pandas drills on groupby, agg, pivot tables, and merges — the repetition that makes aggregation second nature.

4 min readRead
Interview Prep

Product Funnel Analysis: Where Users Drop and How to Prove It in Python

Track users from landing page to purchase in Python — build a funnel, calculate step conversion, and visualise drop-off with Plotly.

5 min readRead
Tutorial

Python Basics Workbook: Control Flow and Functions With 20 Drills

Master Python basics — if/elif/else, for/while loops, functions, and return values — with 20 bite-size drills and solutions.

5 min readRead
Tutorial

Python Fundamentals Master: Strings, Regex, and Data Structures in 30 Questions

Complete Python fundamentals — slicing, f-strings, regex, lists, dicts, and file handling — 30 questions with explained solutions.

4 min readRead
Tutorial

Python String Assignments: 5 Real-World Slicing and Formatting Drills

Practice Python strings on real tasks — email slicer, reverser, cleaner, vowel counter, and f-string formatter with solutions.

4 min readRead
Tutorial

Time Series for Analysts: Trend, Seasonality, and the 7-Line Forecast

Decompose trend and seasonality, resample daily to monthly, smooth with rolling windows, and build a naive forecast in Python.

5 min readRead
Tutorial

Build AI Agents with LangGraph: From State to Tool-Calling Graph

Build autonomous AI agents with LangGraph and Gemini — state, nodes, edges, tool integration, and a compiled graph you can run locally.

5 min readRead
Tutorial

Text Mining for Analysts: TF-IDF Without the Jargon

Turn customer reviews into insights — clean text, score sentiment with TextBlob, and surface complaints with word frequencies in Python.

5 min readRead