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#+LaTeX_CLASS: beamer
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#+LaTeX_HEADER: commentstyle=\color{red}\itshape, stringstyle=\color{darkgreen},
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#+TITLE:
#+AUTHOR: FOSSEE
#+EMAIL: info@fossee.in
#+DATE:
#+DESCRIPTION:
#+KEYWORDS:
#+LANGUAGE: en
#+OPTIONS: H:3 num:nil toc:nil \n:nil @:t ::t |:t ^:t -:t f:t *:t <:t
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*
#+begin_latex
\begin{center}
\vspace{12pt}
\textcolor{blue}{\huge Getting started with Arrays}
\end{center}
\vspace{18pt}
\begin{center}
\vspace{10pt}
\includegraphics[scale=0.95]{../images/fossee-logo.png}\\
\vspace{5pt}
\scriptsize Developed by FOSSEE Team, IIT-Bombay. \\
\scriptsize Funded by National Mission on Education through ICT\\
\scriptsize MHRD,Govt. of India\\
\includegraphics[scale=0.30]{../images/iitb-logo.png}\\
\end{center}
#+end_latex
* Objectives
At the end of this tutorial, you will be able to,
- Create arrays using data.
- Create arrays from lists.
- Perform basic array operations.
- Create identity matrix.
- Use functions zeros(), zeros\_like(), ones(), ones\_like()
* Pre-requisite
Spoken tutorial on -
- Getting started with Lists.
* Overview of Arrays
- Arrays are homogeneous data structures.
- elements have to the same data type
- Arrays are faster compared to lists
- at least /80-100 times/ faster than lists
* ~.shape~ of array
- ~.shape~
To find the shape of the array
: In []: a2.shape
- ~.shape~
returns a tuple of shape
* Exercise 1
Find out the shape of the other arrays(a1, a3, ar) that we have created.
* ~identity()~, ~zeros()~ methods
- ~identity(n)~
Creates an identity matrix, a square matrix of order (n, n) with diagonal elements 1 and others 0.
- ~zeros((m, n))~
Creates an ~m X n~ matrix with all elements 0.
* Learning exercise
Find out about
- ~zeros\_like()~
- ~ones()~
- ~ones\_like()~
* Summary
In this tutorial, we have learnt to,
- Create an array using the ``array()`` function.
- Convert a list to an array.
- Perform some basic operations on arrays like addition,multiplication.
- Use functions like
- .shape
- arrange()
- .reshape
- zeros() & zeros\_like()
- ones() & ones\_like()
* Evaluation
1. ``x = array([1, 2, 3], [5, 6, 7])`` is a valid statement
- True
- False
2. What does the ``ones\_like()`` function do?
(A) Returns an array of ones with the same shape and type as a
given array.
(B) Return a new array of given shape and type, filled with ones.
Read the statements and answer,
- Only statement A is correct.
- Only statement B is correct.
- Both statement A and B are correct.
- Both statement A and B are incorrect.
* Solutions
1. False
x = array([[1, 2, 3], [5, 6, 7]])
2. Statement A- Returns an array of ones with the same shape and type as a
given array.
*
#+begin_latex
\begin{block}{}
\begin{center}
\textcolor{blue}{\Large THANK YOU!}
\end{center}
\end{block}
\begin{block}{}
\begin{center}
For more Information, visit our website\\
\url{http://fossee.in/}
\end{center}
\end{block}
#+end_latex
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