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diff --git a/accessing_parts_of_arrays/slides.org b/accessing_parts_of_arrays/slides.org index 82801ca..98d5923 100644 --- a/accessing_parts_of_arrays/slides.org +++ b/accessing_parts_of_arrays/slides.org @@ -18,7 +18,7 @@ #+LaTeX_HEADER: commentstyle=\color{red}\itshape, stringstyle=\color{darkgreen}, #+LaTeX_HEADER: showstringspaces=false, keywordstyle=\color{blue}\bfseries} -#+TITLE: Accessing parts of arrays +#+TITLE: #+AUTHOR: FOSSEE #+EMAIL: #+DATE: @@ -29,12 +29,35 @@ #+OPTIONS: H:3 num:nil toc:nil \n:nil @:t ::t |:t ^:t -:t f:t *:t <:t #+OPTIONS: TeX:t LaTeX:nil skip:nil d:nil todo:nil pri:nil tags:not-in-toc -* Outline - - Manipulating one and multi dimensional arrays - - Access and change individual elements - - Access and change rows and columns - - Slicing and striding on arrays to access chunks - - Read images into arrays and manipulations +* +#+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, + + - Access and change individual elements of arrays, both one + dimensional and multi-dimensional. + - Access and change rows and columns of arrays. + - Access and change other chunks from an array, using slicing + and striding. + - Read images into arrays and perform processing on them, using + simple array manipulations. +* Pre-requisite + - Spoken tutorial on "Getting started with Arrays". * Sample Arrays #+begin_src python In []: A = array([12, 23, 34, 45, 56]) @@ -46,47 +69,25 @@ [51, 52, 53, 54, 55]]) #+end_src -* Question 1 +* Exercise 1 Change the last column of ~C~ to zeroes. -* Solution 1 - #+begin_src python - In []: C[:, -1] = 0 - #+end_src -* Question 2 +* Exercise 2 Change ~A~ to ~[11, 12, 13, 14, 15]~. -* Solution 2 - #+begin_src python - In []: A[:] = [11, 12, 13, 14, 15] - #+end_src * squares.png #+begin_latex \begin{center} \includegraphics[scale=0.6]{squares} \end{center} #+end_latex -* Question 3 +* Exercise 3 - obtain ~[22, 23]~ from ~C~. - obtain ~[11, 21, 31, 41]~ from ~C~. - - obtain ~[21, 31, 41, 0]~. -* Solution 3 - #+begin_src python - In []: C[1, 1:3] - In []: C[0:4, 0] - In []: C[1:5, 0] - #+end_src -* Question 4 + - obtain ~[21, 31, 41, 0]~. +* Exercise 4 Obtain ~[[23, 24], [33, -34]]~ from ~C~ -* Solution 4 - #+begin_src python - In []: C[1:3, 2:4] - #+end_src -* Question 5 +* Exercise 5 Obtain the square in the center of the image -* Solution 5 - #+begin_src python - In []: imshow(I[75:225, 75:225]) - #+end_src -* Question 6 +* Exercise 6 Obtain the following #+begin_src python [[12, 0], [42, 0]] @@ -99,25 +100,57 @@ In []: C[::4, 1:4] #+end_src * Summary - You should now be able to -- - - Manipulate single \& multi dimensional arrays - - Access and change individual elements - - Access and change rows and columns - - Slice and stride on arrays + In this tutorial, we have learnt to, + + - Manipulate single & multi dimensional arrays. + - Access and change individual elements by using their index numbers. + - Access and change rows and columns of arrays by specifying the row + and column numbers. + - Slice and stride on arrays. - Read images into arrays and manipulate them. -* Thank you! +* Evaluation + 1. Given the array, ``A = array([12, 15, 18, 21])``, how do we access + the element ``18``? + + + 2. Given the array, + + C = array([[10, 11, 12, 13], + [20, 21, 22, 23], + [30, 31, 32, 33], + [40, 41, 42, 43]]) + + Obtain the elements, ``[[21, 22], [31, 32]]`` + + + 3. Given the array, + + C = array([[10, 11, 12, 13], + [20, 21, 22, 23]]) + + Change the array to + + C = array([[10, 11, 10, 11], + [20, 21, 20, 21]]) +* Solutions + 1. A[ 2 ] + + 2. B[1:3, 1:3] + + 3. B[:2, 2:] = B[:2, :2] + +* #+begin_latex \begin{block}{} \begin{center} - This spoken tutorial has been produced by the - \textcolor{blue}{FOSSEE} team, which is funded by the + \textcolor{blue}{\Large THANK YOU!} \end{center} + \end{block} +\begin{block}{} \begin{center} - \textcolor{blue}{National Mission on Education through \\ - Information \& Communication Technology \\ - MHRD, Govt. of India}. + For more Information, visit our website\\ + \url{http://fossee.in/} \end{center} \end{block} #+end_latex - |