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How to Read a CSV File from Amazon S3 Using Python (With Headers and Rows Displayed)

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  Introduction If you’re working with cloud data, especially on AWS, chances are you’ll encounter data stored in CSV files inside an Amazon S3 bucket . Whether you're building a data pipeline or a quick analysis tool, reading data directly from S3 in Python is a fast, reliable, and scalable way to get started. In this blog post, we’ll walk through: Setting up access to S3 Reading a CSV file using Python and Boto3 Displaying headers and rows Tips to handle larger datasets Let’s jump in! What You’ll Need An AWS account An S3 bucket with a CSV file uploaded AWS credentials (access key and secret key) Python 3.x installed boto3 and pandas libraries installed (you can install them via pip) pip install boto3 pandas Step-by-Step: Read CSV from S3 Let’s say your S3 bucket is named my-data-bucket , and your CSV file is sample-data/employees.csv . ✅ Step 1: Import Required Libraries import boto3 import pandas as pd from io import StringIO boto3 is...
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How to Create an Array and Its Types in Python

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Python supports various array types. Here is a list of arrays and how to create examples for your reference. 

What is an array?


A Python array is a class that mimics the array type of other languages and offers efficiency in storage, exchanging that for flexibility.

How to create an array


Here is the syntax to create an array:

data = array('f', [12.8, 5.4, 8.0, 8.0, 9.21, 3.14])


It creates an array of 6 floating point numbers; the type is indicated by the 'f' as the first parameter to the constructor. This concept is unlike the Python norm of types being dynamic and malleable. An array is an array of one kind of thing, and an array can only hold a restricted set of types.


Array types

Types of arrays

Here is a list of arrays:

'b' A C++ char type
'B' A C++ unsigned char type
'i': A C++ int type
'l': A C++ long type
'f': A C++ float type
'd': A C++ double type

What is an array type?

Arrays are class objects and are provided in the built-in module array, which must be imported:

from array import array

An array is a sequence type and has the basic properties and operations that Python provides for all sequence types. Array elements can be assigned to and can be used in expressions, and arrays can be searched and extended like other sequences.

Tips: I have referred some best books and Udemy course. I am giving here for your ready reference. The best Udemy course is Python Bootcamp and the best Python book is Python pocket primer.
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