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<!doctype html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no">
<title>Introduction to Programming with Python</title>
<link rel="stylesheet" href="css/reveal.css">
<link rel="stylesheet" href="css/theme/cci.css">
<link href="https://fonts.googleapis.com/css?family=Poppins" rel="stylesheet">
<!-- Theme used for syntax highlighting of code -->
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<script>
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document.getElementsByTagName( 'head' )[0].appendChild( link );
</script>
</head>
<body>
<div class="reveal">
<!-- Header logo -->
<!--img style="position:fixed;top:1em;right:1em;" src="img/logo_cci.png" width="15%"-->
<!-- Slide Title -->
<header style="position: absolute;top: 1em; left: 1em; z-index:10;"></header>
<div class="slides">
<section data-menu-title="Title">
<h2>Introduction to Programming with Python</h2>
<h4>Erick Martins Ratamero<br>Research Fellow</h4>
</section>
<section data-menu-title="Introduction" data-state="intro0">
<h2>Hello</h2>
<br/>
<br/>
<br/>
<a href="https://twitter.com/erickratamero" target="_blank">@erickratamero</a>
</section>
<section data-state="intro0">
<h2>
<b>Acknowledgements</b>
</h2>
<ul>
<li>Philo van Kemenade (<a href="https://twitter.com/phivk">@phivk</a>) from whom I "stole" the general structure of the presentation and some of the images </li>
<li>(original at <a href="https://slides.com/phivk/intro2python">https://slides.com/phivk/intro2python</a>)</li>
</ul>
</section>
<section data-state="intro0">
<h2>
<b>This Workshop</b>
</h2>
<ul>
<li>Building blocks</li>
<li>Putting the pieces together</li>
<li>Writing complete structures</li></ul>
</section>
<section data-state="intro0">
<h2>These Slides</h2>
<br/>
<br/>
<br/>
<a href="http://tiny.cc/camdupython" target="_blank">tiny.cc/camdupython</a>
<br/>
</section>
<section data-menu-title="Python" data-state="python">
<h1>
Let's talk about Python
</h1>
</section>
<section data-state="python">
<h2>Talking Python</h2>
<div class="absolute-element" style="position: absolute; width: 413px; height: 46px; z-index: 4; left: 490px; top: 308px; max-height: none; max-width: none;">One of Python's most
attractive features
</div>
<img src="img-py/language_spectrum_whitebg.png" style="width: 423.659px; height: 449.582px; max-height: none; max-width: none; position: absolute; z-index: 4; left: 10px; top: 128px;" class="absolute-element"/>
</section>
<section data-state="python">
<h2 >Two Modes of Operation</h2>
<div class="absolute-element" style="position: absolute; width: 281px; height: 195px; z-index: 7; left: 581px; top: 131px;">
<p>
<span class="s1">
<b>
Scripting Mode
</b>
</span>
</p>
<ul>
<li>
<span>
Code in file
</span>
</li>
<li>
<span>
Save & load programs
</span>
</li>
<li>
<span>
More control
</span>
</li>
</ul>
</div>
<div class="absolute-element" style="position: absolute; width: 281.479px; height: 195px; z-index: 8; left: 74px; top: 132px; max-height: none; max-width: none;">
<p>
<span class="s1">
<b>
Interactive Mode
</b>
</span>
</p>
<ul>
<li>
<span>
Terminal-based
</span>
</li>
<li>
<span>
Direct feedback
</span>
</li>
<li>
<span>
Try out code
</span>
</li>
</ul>
</div>
<img src="img-py/python_modes.png" class="absolute-element" style="position: absolute; max-height: none; max-width: none; width: 927.256px; height: 502.582px; z-index: 4; left: 7px; top: 136px;"/>
<br/>
</section>
<section data-state="python">
<h2>Setting Up</h2>
<p>Download Thonny from <a href="https://thonny.org" target="_blank">
https://thonny.org</a></p>
<p>Install Thonny</p>
<p>Done!</p>
</section>
<section data-state="python">
<h2>Getting help</h2>
<pre><code>help()</code></pre>
<p>(then Q for quit)</p>
<p>Documentation at <a href="https://docs.python.org/3/" target="_blank">docs.python.org/3</a> </p>
<p>Just googling stuff is surprisingly helpful (and what everyone does)</p>
</section>
<section data-state="python">
<h2>Syntax</h2>
</section>
<section data-state="python">
<h2> Some of it you already know</h2>
<img src="img-py/calculator.png"/>
<p>Python as a calculator
</p>
</section>
<section data-menu-title="Building Blocks" data-state="bb">
<h1>
Building Blocks
</h1>
</section>
<section data-state="bb">
<h2>VARIABLES</h2>
<img src="img-py/var-name-red.png"/>
<br/>
<font color="#e06666">
<b><i>Variables</i></b></font> store <i>values</i> under a specified name
<br/>
</section>
<section data-state="bb">
<h2>VARIABLES</h2>
<img src="img-py/vars-nametags.png"/>
</section>
<section data-state="bb">
<h2>Assigning variables in python</h2>
<pre><code>name = "Erick"
gender = "male"
height = 1.73 </code></pre>
</section>
<section data-state="bb">
<h2>Types of variables</h2>
<p>Variables can store values of different <b><i>types</i></b>:</p>
<p style="text-align: left;">
<font color="#e06666"><b>string</b></font> - a sequence of characters, comprising text
</p>
<pre><code>"a", "London", 'X', 'General Assembly'</code></pre>
<p style="text-align: left;">
<font color="#e06666"><b>int</b></font> - an integer, or whole number
</p>
<pre><code>1, 5, 9999, -7</code></pre>
<p style="text-align: left;">
<font color="#e06666"><b>float</b></font> - a floating point number (using a decimal point)
</p>
<pre><code>3.14, 1.68, 1.0</code></pre>
<p style="text-align: left;">
<font color="#e06666"><b>bool</b></font> - boolean; binary true or false values
</p>
<pre><code>True, False</code></pre>
</section>
<section data-state="bb">
<h2>Changing types</h2>
<p>'Casting' a variable to another type</p>
<p>
<br/>
</p>
<pre><code>int("42")
float("1.69")
str(1.5) </code></pre>
<br/>
</section>
<section data-state="bb">
<h2>Exercise
</h2>
<br/>
Choose 4 things in this room and create variables of 4 different types based on them
</section>
<section data-state="bb">
<h2>Operators</h2>
<p>
<span class="s1">You can process the values in your variables by
<b>
<i>
<font color="#e06666">operators</font>
</i>
</b>:
</span>
</p>
<table width="100%" cellspacing="10" cellpadding="5" border="0">
<tbody>
<tr>
<td>
<font style="font-size: 30px;" color="#e06666">
<b>=</b>
</font>
</td>
<td>
<font style="font-size: 30px;">Assignment: assign a value to a variable </font>
</td>
</tr>
<tr>
<td>
<font style="font-size: 30px;" color="#e06666">
<b>==</b>
</font>
</td>
<td>
<font style="font-size: 30px;">Comparison: are two variables equal?</font>
</td>
</tr>
<tr>
<td>
<font style="font-size: 30px;" color="#e06666">
<b>!=</b>
</font>
</td>
<td>
<font style="font-size: 30px;">Comparison: are two variables not equal?</font>
</td>
</tr>
<tr>
<td>
<p class="p1">
<span class="s1">
<b>
<font style="font-size: 30px;" color="#e06666"><, >, <=, >=</font>
</b>
</span>
</p>
</td>
<td>
<font style="font-size: 30px;">Less-than, greater-than, less or equal, greater or equal</font>
</td>
</tr>
<tr>
<td>
<font style="font-size: 30px;" color="#e06666">
<b>+, -, *, /</b>
</font>
</td>
<td>
<font style="font-size: 30px;">Mathematical operators</font>
</td>
</tr>
<tr></tr>
<tr>
<td>
<font style="font-size: 30px;" color="#e06666">
<b>and, or</b>
</font>
</td>
<td>
<font style="font-size: 30px;">Logical operators</font>
</td>
</tr>
</tbody>
</table>
</section>
<section data-state="bb">
<h2>Specific behaviour depends on data type
<br/>
</h2>
<div style="width: 421px; height: 275px; max-height: none; max-width: none; position: absolute; z-index: 4; left: 535px; top: 154px;">
<pre><code class="python">>>> start = "Lon"
>>> start
'Lon'
>>> end = "don"
>>> start + end
'London'
>>> start + start + end
'LonLondon'
>>> town = 3 * start + end
>>> town
'LonLonLondon'</code></pre>
</div>
<div style="width: 421px; height: 275px; max-height: none; max-width: none; position: absolute; z-index: 4; left: 0px; top: 154px;">
<pre><code class="python">>>> 1 + 1
2
>>> cats = 2
>>> cats
2
>>> dogs = 3
>>> cats == dogs
False
>>> cats < dogs
True
>>> dogs + 1
4
>>> dogs
3
>>> dogs = dogs + 1
>>> dogs
4
>>> pets = cats + dogs
>>> pets
6</code></pre>
</div>
<br/>
</section>
<section data-state="bb">
<h2>
Questions?
</h2>
</section>
<section data-state="bb">
<h2>Exercise</h2>
<p>
Create two
<font color="#e06666">
<i>string variables</i>
</font>:
</p>
<p>
<i>first</i> for your first name and <i>last</i> for your last name.
</p>
<p>
Can you make your full name by combining <i>first</i> and <i>last</i>?
</p>
<p>
Bonus:
</p>
<p>
What happens if we compare <i>first</i> and <i>last</i> with the ‘<' and ‘>' operators?
</p>
<p>
Why?
</p>
<p>
<font color="#e06666">
(Cheating encouraged)
</font>
</p>
</section>
<section data-state="bb">
<h2>Extra exercises</h2>
<a href="https://www.w3resource.com/python-exercises/python-basic-exercises.php">https://www.w3resource.com/python-exercises/python-basic-exercises.php</a>
</section>
<section data-state="bb">
<h2>
Collections
</h2>
</section>
<section data-state="bb">
<h2>Collections of Values</h2>
Values can also be stored in a
<font color="#e06666">
<b>
<i>collection</i>
</b>
</font>:
<p><b>List</b></p>
<p><b>Dictionary</b></p>
</section>
<section data-state="bb">
<h2>Lists</h2>
<p>
We can store multiple values in a <b><i><font color="#e06666">list</font>:</i></b>
</p>
<pre><code class="python">>>> l = [1,3,9,4,884328881]
>>> n = ['first', 'second', 'third', 'fourth']
>>> m = l + n
>>> m
[1, 3, 9, 4, 884328881, 'first', 'second', 'third', 'fourth']</code></pre>
<br/>A list is a ordered sequence of items (between [...]) each with their own index:
<pre><code class="python">>>> m[0]
1
>>> m[8]
'fourth' </code></pre>
<br/>
</section>
<section data-state="bb">
<h2>Indices</h2>
<img src="http://i.stack.imgur.com/vIKaD.png"/>
</section>
<section data-state="bb">
<h2>Cool things you can do with lists
<br/>
</h2>
<pre><code class="python">
>>> l = list(range(10))
>>> l
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> l[1:5]
[1, 2, 3, 4]
>>> l[:5]
[0, 1, 2, 3, 4]
>>> del l[5:]
>>> l
[0, 1, 2, 3, 4]
>>> l.append(5)
>>> l
[0, 1, 2, 3, 4, 5]
>>> l.reverse()
>>> l
[5, 4, 3, 2, 1, 0]
>>> 5 in l
True
</code></pre>
<a href="https://docs.python.org/3/tutorial/datastructures.html#more-on-lists" target="_blank">https://docs.python.org/3/tutorial/datastructures.html#more-on-lists</a>
<br/>
</section>
<section data-state="bb">
<h2>Bonus</h2>
Lists are sequences, and so are strings
<pre><code class="python">>>> s = "General Assembly"
>>> s[0]
'G'
>>> s[:7]
'General' </code></pre>
</section>
<section data-state="bb">
<h2>Dictionaries</h2>
Dictionaries store <i><font color="#e06666">key</font>: <font color="#3d85c6">value</font>
</i> pairs associatively.
<pre><code class="python">>>> personX = {'first':'Erick', 'last':'Ratamero', 'twitter':'@erickratamero'}
>>> personX['first']
'Erick'
>>> personX['age'] = 32
>>> personX
{'twitter': '@erickratamero', 'last': 'Ratamero', 'age': 32, 'first': 'Erick'}
>>> for i in personX.items():
... print(i)
...
('first', 'Erick')
('last', 'Ratamero')
('twitter', '@erickratamero')
</code></pre>
<br/>
</section>
<section data-state="bb">
<h2>some things you can do with Dictionaries
<br/>
</h2>
<pre><code class="python">>>> list(personX.keys())
['twitter', 'last', 'first']
>>> list(personX.values())
['@erickratamero', 'Ratamero', 'Erick']</code></pre>
</section>
<section data-state="bb">
<h2>
Questions?
</h2>
</section>
<section data-state="bb">
<h2>Exercise</h2>
Create a dictionary to represent yourself (or someone else) with some attributes (e.g. hometown, favourite film, height)
<p>Bonus:</p>
Add a <b><i>list</i></b> of interests to the <b><i>dictionary</i></b>. What do you use as <b><i>key</i></b>, what do you use as <i><b>value</b></i>?
<font color="#e06666">
(Cheating encouraged)
</font>
</section>
<section data-state="bb">
<h2>Extra exercises</h2>
<a href="https://www.w3resource.com/python-exercises/list/">https://www.w3resource.com/python-exercises/list/</a><br>
<a href="https://www.w3resource.com/python-exercises/dictionary/">https://www.w3resource.com/python-exercises/dictionary/</a>
</section>
<section data-menu-title="Putting the pieces together" data-state="pp">
<h1>
Putting the pieces together
</h1>
</section>
<section data-state="pp">
<h1>
Loops
</h1>
</section>
<section data-state="pp">
<h2>For Loops</h2>
<p>
You use <i><font color="#e06666">loops</font></i> to repeat a statement.
</p>
<p>
A <b><i><font color="#e06666">for-loop</font></i></b> is useful when you know how many times you want to repeat an action (e.g. for every item in a list)
</p>
<pre><code class="python">for item in sequence:
do something with item</code></pre>
<br/>
<br/>Mind the <i>Indentation</i>
</section>
<section data-state="pp">
<h2>For Loops</h2>
<br/>
<img src="img-py/python_for_loop.jpg"/>
</section>
<section data-state="pp">
<h2>For Loops</h2>
<p>for example:
</p>
<pre><code class="python">>>> ages = [18, 21, 16, 12]
>>> for age in ages:
.... print(age)
....
18
21
16
12 </code></pre>
<br/>
<a href="http://pythontutor.com/visualize.html#code=ages+%3D+%5B18,+21,+16,+12%5D%0Afor+age+in+ages%3A%0A++++print(age%29&mode=display&origin=opt-frontend.js&cumulative=false&heapPrimitives=false&textReferences=false&py=3&rawInputLstJSON=%5B%5D&curInstr=0" target="_blank">Visualise this code in action</a>
<br/>
</section>
<section data-state="pp">
<h2>While Loops</h2>
<p>A <b><i><font color="#e06666">while-loop</font></i></b> is useful when you don’t know when you want to stop looping yet.
</p>
<p>A while-loop statement checks a <i>condition</i> and loops until the condition is no longer satisfied.
</p>
<pre><code class="python">while condition true:
do something</code></pre>
</section>
<section data-state="pp">
<h2>While loops</h2>
<img src="img-py/python_while_loop.jpg"/>
</section>
<section data-state="pp">
<h2>While Loops</h2>
<p>for example:
</p>
<pre><code class="python">>>> gas = 42
>>> while gas > 0:
... print("Vroom!")
... gas = gas - 10
...
Vroom!
Vroom!
Vroom!
Vroom!
Vroom! </code></pre>
<a href="http://pythontutor.com/visualize.html#code=gas+%3D+42%0Awhile+gas+%3E+0%3A%0A++++print(%22Vroom!%22%29%0A++++gas+%3D+gas+-+10&mode=display&origin=opt-frontend.js&cumulative=false&heapPrimitives=false&textReferences=false&py=3&rawInputLstJSON=%5B%5D&curInstr=0" target="_blank">
Visualise this code in action
</a>
</section>
<section data-state="pp">
<h2>Exercise</h2>
<p>
Write a program that prints all even numbers between 0 and 50
</p>
<p>
Write a program that prints the first 10 odd numbers
</p>
<font color="#e06666">
(Cheating encouraged)
</font>
</section>
<section data-state="pp">
<h2>
Conditional Statements
</h2>
</section>
<section data-state="pp">
<h2>Conditional statements</h2>
<p><b><i><font color="#e06666">Conditional statements</font></i></b> enable you to deal with multiple options.
</p>
<p>
A part of your code is executed based on the truth value of a condition. You perform conditional checks with: <b>if, elif, else</b>
</p>
<pre><code class="python">if condition:
action
elif other condition: #optional
other action
else:
final action</code></pre>
<pre><code class="python">>>> age = 17
>>> if age < 18:
... print("no drinks for you")
...
no drinks for you</code></pre>
</section>