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diff --git a/manipulating-lists/slides.org b/manipulating-lists/slides.org
index 5d2ce93..c0eea62 100644
--- a/manipulating-lists/slides.org
+++ b/manipulating-lists/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: Manipulating Lists
#+AUTHOR: FOSSEE
#+EMAIL:
#+DATE:
@@ -28,83 +28,54 @@
#+LANGUAGE: en
#+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
+#+STARTUP: align fold nodlcheck hidestars oddeven lognotestate
* 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
-* Sample Arrays
- #+begin_src python
- In []: A = array([12, 23, 34, 45, 56])
-
- In []: C = array([[11, 12, 13, 14, 15],
- [21, 22, 23, 24, 25],
- [31, 32, 33, 34, 35],
- [41, 42, 43, 44, 45],
- [51, 52, 53, 54, 55]])
-
- #+end_src
+ In this session we shall be looking at
+ - Concatenating lists
+ - Obtaining parts of lists
+ - Sorting lists
+ - Reversing lists
* Question 1
- Change the last column of ~C~ to zeroes.
+ Obtain the primes less than 10, from the list ~primes~.
* Solution 1
#+begin_src python
- In []: C[:, -1] = 0
- #+end_src
+ primes[0:4]
+ #+end_src python
+* Slicing
+ #+begin_src python
+ p[start:stop]
+ #+end_src python
+ - Returns all elements of ~p~ between ~start~ and ~stop~
+ - The element with index equal to ~stop~ is *not* included.
* Question 2
- Change ~A~ to ~[11, 12, 13, 14, 15]~.
+ Obtain all the multiples of three from the list ~num~.
* 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
+ num[::3]
+ #+end_src python
* Question 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 ~[[23, 24], [33, -34]]~ from ~C~
-* Solution 4
+ Given a list of marks of students in an examination, obtain a list
+ with marks in descending order.
#+begin_src python
- In []: C[1:3, 2:4]
- #+end_src
-* Question 5
- Obtain the square in the center of the image
-* Solution 5
+ marks = [99, 67, 47, 100, 50, 75, 62]
+ #+end_src python
+* Solution 3
#+begin_src python
- In []: imshow(I[75:225, 75:225])
- #+end_src
-* Question 6
- Obtain the following
+ sorted(marks)[::-1]
+ #+end_src python
+OR
#+begin_src python
- [[12, 0], [42, 0]]
- [[12, 13, 14], [0, 0, 0]]
- #+end_src
+ sorted(marks, reverse=True)
+ #+end_src python
-* Solution 6
- #+begin_src python
- In []: C[::3, 1::3]
- In []: C[::4, 1:4]
- #+end_src
* Summary
- You should now be able to --
- - Manipulate 1D \& Multi dimensional arrays
- - Access and change individual elements
- - Access and change rows and columns
- - Slice and stride on arrays
- - Read images into arrays and manipulate them.
+ In this tutorial session we learnt
+ + Obtaining parts of lists using slicing and striding
+ + List concatenation
+ + Sorting lists
+ + Reversing lists
+
* Thank you!
#+begin_latex
\begin{block}{}