[MUSIC] So next, we're going to inspect
some columns of our data set. So let me, let's inspect some columns of the data set. So let's take a look at it. So if I type sf['Country'], what it's gonna do is select
a column country, and since I don't do anything to it,
I don't set it equal to anything. It's just going to print it. Now, it says United States,
Canada, England, USA, Poland, United States, Switzerland. So, that's the whole column,
but printed horizontally. Now, let's look at another column. So, for example,
let's look at the column age, so, sf.age. I'm just gonna look at it. So I have, the column is 24,
23, 22, 23, 23, 22, 25. Same one we did a visualization up here. Now we can take the same column sf.age and
do some computations on it. So if you type .mean, it's not
saying that column is a mean column, but actually computing
the mean of that column. Which, the mean age is 23.142857,
and so on. Now, we can compute, for
example the max age. So, as of age, and let's see max. And again you get 25, that's maximum age. Now, this is some prequel stuff,
but let's do more. Let's create new columns. In our SFrame. So, when you're doing machine learning,
often taking columns and transforming them, creating new ones,
this is called feature engineering. We will do a bunch of those. I'm gonna do now,
a creation of a new column. So, let's go back and
print the SFrame, and you see that there's a First Name
column and there's a Last Name column. There's no full name column. Let's say you want to create a new
full name column, it's pretty easy. I wanna say sf,
our SFrame of Full Name, so there's gonna be a column
called Full Name. And what is that column equal to? Well, it's just a concatenation
of first name and last name. And in Python, it's really easy to take
strings and concatenate them together. All you have to do is put a plus sign. So we can do sf['Full Name'] is gonna be the First Name column, so ['First Name'], and then I'm gonna put a space between it,
so plus the space, plus the last name column. So, Last Name. Now, this is pretty cool. I just create a new feature, new column, called full name which is just
the first name space last name. It's very easy to do
these things in Python, especially if you don't have typos. I see that this is Fist Name
instead of First Name. So, and there you go. So, now if you go back and
show the SFrame again, you'll see there is a new column called
Full Name has been placed at the end. So Bob Smith is the first full name there. Now, you can do all sorts
of interesting things. So, for
example you could take the age column and I'm not gonna create a new problem. I'm just gonna do add 2
here to this age column. And you'll see that it's just
gonna add 2 to every element. And so,
you can do these kinds of operations. For example, you can do age and multiply it by the column age again. Now what happens when you do that? Age times age? You're gonna get age
squared in every element. And you get 556, 529 and so on. [MUSIC]