Data Science — Exploratory Data Analysis
Big data characteristics
- Volume: Large amounts
- Velocity: Fast generation
- Variety: Different types
Hadoop ecosystem
# HDFS
hdfs dfs -put localfile /hdfs/path
hdfs dfs -cat /hdfs/path/file
# MapReduce
hadoop jar hadoop-streaming.jar \
-mapper mapper.py \
-reducer reducer.py \
-input /input \
-output /output
Spark
from pyspark.sql import SparkSession
spark = SparkSession.builder.appName("myapp").getOrCreate()
# Read data
df = spark.read.csv("data.csv", header=True)
# Transformations
df_filtered = df.filter(df["age"] > 25)
df_grouped = df.groupBy("category").count()
# Actions
df_grouped.show()
Data lake vs data warehouse
| Feature | Data Lake | Data Warehouse |
|---|---|---|
| Structure | Raw | Processed |
| Schema | On read | On write |
| Cost | Lower | Higher |
| Flexibility | High | Low |
Best practices
- Choose right tool
- Optimize queries
- Monitor performance
- Scale as needed
Mini Practice
- Process data with Spark
- Query with HDFS
- Build ETL pipeline
- Optimize performance
Up Next
Continue with Spark - Distributed computing.
Related Topics
Frequently Asked Questions about Exploratory Data Analysis
What is Exploratory Data Analysis in Data Science?
Exploratory Data Analysis is a fundamental concept in Data Science. This lesson explains it step by step with clear examples, making it easy for beginners to understand.
How do I learn Exploratory Data Analysis?
Start by reading the explanation above, then try the code examples. Practice by modifying the examples and experimenting with different values. Hands-on practice is the best way to learn Exploratory Data Analysis.
Why is Exploratory Data Analysis important in Data Science?
Exploratory Data Analysis is essential for Data Science development. Understanding this concept will help you write better code and solve real-world problems more effectively.