1
00:00:00,000 --> 00:00:04,238
[MUSIC]

2
00:00:04,238 --> 00:00:07,688
>> Today we're going to talk about
two really exciting tools for

3
00:00:07,688 --> 00:00:12,680
programming machine learning algorithms,
and also useful in data science.

4
00:00:12,680 --> 00:00:14,830
One is the Python programming language,
and

5
00:00:14,830 --> 00:00:17,470
the other one is what's
called the iPython Notebook.

6
00:00:17,470 --> 00:00:22,230
At this point, I'll assume that you have
already installed Python in your system.

7
00:00:22,230 --> 00:00:24,770
You've gone through those
steps of installation.

8
00:00:24,770 --> 00:00:28,770
And now I'm just gonna go over
a few tips to get started.

9
00:00:28,770 --> 00:00:33,760
There's lots and lots of resources
available online for you to explore and

10
00:00:33,760 --> 00:00:36,500
familiarize yourself with all
the techniques that you need to do.

11
00:00:36,500 --> 00:00:39,110
But really, I think it would be fun for
us to go over this together,

12
00:00:39,110 --> 00:00:41,780
since this is a really,
really useful tool.

13
00:00:41,780 --> 00:00:45,000
And something that makes
a tremendous difference in practice.

14
00:00:45,000 --> 00:00:48,150
When you first call iPython Notebook,
you are faced with something like this.

15
00:00:48,150 --> 00:00:50,440
It's basically a version
of your directory,

16
00:00:50,440 --> 00:00:53,260
with all the files in the directory.

17
00:00:53,260 --> 00:00:56,300
There's some data files that I have,
as well as some

18
00:00:56,300 --> 00:01:00,920
iPython Notebooks I have created
earlier and some other data net file.

19
00:01:00,920 --> 00:01:03,110
This is more like a file browser.

20
00:01:03,110 --> 00:01:06,280
So what we're gonna do is
start a whole new notebook.

21
00:01:07,330 --> 00:01:10,230
So I am gonna go New, Python 2,

22
00:01:10,230 --> 00:01:13,820
since we're gonna have a notebook
that is a Python notebook.

23
00:01:13,820 --> 00:01:16,000
And welcome this is iPython notebook.

24
00:01:16,000 --> 00:01:16,970
This store is gonna run for

25
00:01:16,970 --> 00:01:22,000
a few years now and has really changed
how we build machine learning and

26
00:01:22,000 --> 00:01:27,335
data science algorithms and
how we communicate with others.

27
00:01:27,335 --> 00:01:28,890
It's a really useful tool.

28
00:01:28,890 --> 00:01:32,080
It blends two things that I love, Python,

29
00:01:32,080 --> 00:01:35,770
a simple scripting programming
language with Wiki pages,

30
00:01:35,770 --> 00:01:38,440
things which make it reasonably
easy to communicate with others.

31
00:01:38,440 --> 00:01:42,230
So, Python plus Wiki pages
is the iPython notebook.

32
00:01:42,230 --> 00:01:45,810
So today I'm gonna both show
you the iPython Notebook and

33
00:01:45,810 --> 00:01:49,650
also gonna show you some tips and
tricks in Python just to get started,

34
00:01:49,650 --> 00:01:53,430
assuming that you can program in Python or
in other programming languages.

35
00:01:53,430 --> 00:01:57,830
So you've run IPython Notebook and
you started a fresh new one.

36
00:01:57,830 --> 00:01:59,710
Let me just walk you over the interface.

37
00:02:00,720 --> 00:02:03,810
So at the very top here is
the title of the notebook.

38
00:02:03,810 --> 00:02:06,350
And we're going to change
it to something else.

39
00:02:06,350 --> 00:02:11,978
So I'm going to change
it to Getting Started

40
00:02:11,978 --> 00:02:19,549
with iPython Notebook.

41
00:02:21,270 --> 00:02:21,840
And there you go.

42
00:02:21,840 --> 00:02:25,260
We have a new notebook,
and that's the title.

43
00:02:25,260 --> 00:02:29,120
And so this notebook is kind
of like a console for Python.

44
00:02:29,120 --> 00:02:33,450
But also it allows you to save the pages
that you generate, and include text and

45
00:02:33,450 --> 00:02:34,180
images in that.

46
00:02:34,180 --> 00:02:36,660
And we're gonna play with all
of that during this course,

47
00:02:36,660 --> 00:02:38,340
because it's really useful.

48
00:02:38,340 --> 00:02:41,380
It has a menu here that
allows you to do things like

49
00:02:41,380 --> 00:02:45,685
save the file that you have and
load a new one, edit, copy,

50
00:02:45,685 --> 00:02:49,760
add new cells, and
we're gonna talk about those soon.

51
00:02:49,760 --> 00:02:51,140
But let's just get started.

52
00:02:51,140 --> 00:02:52,660
So let's get started with Python.

53
00:02:52,660 --> 00:02:56,720
I want to click on one of the cells, which
is kind of like an entry in a console.

54
00:02:56,720 --> 00:02:59,700
And I'm going to type my
first Python function.

55
00:02:59,700 --> 00:03:02,050
So the first function I'm
going to do is just print.

56
00:03:02,050 --> 00:03:06,820
So I'm going to print a string and
strings in Python can be single quotes or

57
00:03:06,820 --> 00:03:07,980
double quotes, is up to you.

58
00:03:07,980 --> 00:03:13,750
And the string I'm going to
print is the famous hello world.

59
00:03:15,280 --> 00:03:20,150
And when I press Shift-Enter,
it executes a cell so

60
00:03:20,150 --> 00:03:22,050
you have to remember to press Shift-Enter.

61
00:03:22,050 --> 00:03:24,040
We'll talk about pressing
just Enter in a second.

62
00:03:26,110 --> 00:03:28,320
And after executing, it says Hello World.

63
00:03:29,980 --> 00:03:35,630
So now,
let's take a ride on iPython Notebook and

64
00:03:35,630 --> 00:03:41,800
some of the Python functions that we're
interested in using during these courses.

65
00:03:41,800 --> 00:03:46,590
So the first piece of iPython Notebook
is that you can include text, and

66
00:03:46,590 --> 00:03:51,180
really well-formatted text, so
there's two ways of accessing text cells.

67
00:03:51,180 --> 00:03:56,862
So the first one is to
go over here to cell,

68
00:03:56,862 --> 00:04:00,950
cell type and call it markdown.

69
00:04:00,950 --> 00:04:02,930
And then you click on it and
you can start writing.

70
00:04:02,930 --> 00:04:05,630
And it's really a mark down
language kind of like Wikipages.

71
00:04:05,630 --> 00:04:09,976
So if I put a pound here,
I can do a header,

72
00:04:09,976 --> 00:04:14,370
#Getting started with Python.

73
00:04:17,420 --> 00:04:19,470
Oops.
And now instead of pressing Shift+Enter,

74
00:04:19,470 --> 00:04:22,400
we press regular Enter,
it gives you a multiline cell.

75
00:04:22,400 --> 00:04:23,450
So Enter.

76
00:04:23,450 --> 00:04:25,050
Let's get started with Python.

77
00:04:25,050 --> 00:04:27,412
And let's do a sub-header now.

78
00:04:27,412 --> 00:04:31,318
The first thing we're gonna assume
is what you have done so far.

79
00:04:31,318 --> 00:04:38,251
So we have done the following.

80
00:04:38,251 --> 00:04:40,360
So just press enter.

81
00:04:40,360 --> 00:04:41,030
Here's a list.

82
00:04:41,030 --> 00:04:45,094
We've done, we've installed Python,

83
00:04:45,094 --> 00:04:49,936
the Python programming language.

84
00:04:49,936 --> 00:04:54,906
We've started

85
00:04:54,906 --> 00:05:01,413
iPython Notebook.

86
00:05:01,413 --> 00:05:02,810
And okay.

87
00:05:02,810 --> 00:05:04,650
So that did not work so well.

88
00:05:04,650 --> 00:05:06,510
Okay.
I executed it, it's not quite right.

89
00:05:06,510 --> 00:05:09,920
Let me see what I forgot, so
I can double-click on it and edit.

90
00:05:09,920 --> 00:05:11,910
I forgot to put a space here.

91
00:05:11,910 --> 00:05:14,920
So Space between the different lines.

92
00:05:14,920 --> 00:05:16,240
So we install iPython, and

93
00:05:16,240 --> 00:05:19,250
we start the iPython Notebook,
this is what we have done so far.

94
00:05:21,070 --> 00:05:26,044
And now if I press Shift + Enter,
and you can see now we have a list.

95
00:05:26,044 --> 00:05:30,299
[MUSIC]