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In this video we'll take another look

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at that enumerate function that

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we just demonstrated
in the preceding video.

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This time in the context of

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the script fig05_01.py.

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Let's go ahead and run that and see

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what the results look like.

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So basically what we're going to do

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is we're going to take a list of values,

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which you see in the middle column here,

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and we're going to use
the enumerate function

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to help us produce the
output that you see here

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consisting of the index
number of each value,

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the actual value, and
then a bar of asterisks

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representing that value.

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So basically a primitive bar chart.

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And we're going to show
you later on in this lesson

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much nicer looking visualizations

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that produce bar charts
automatically for you.

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So we'll take a look at that in

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the intro to data science section
at the end of this lesson.

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So let's switch over to the script

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that actually produces the
output you just saw there.

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Again anytime we create a script

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we're going to tell you
the name of the file

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in a comment at the beginning so you can

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find that script in the
corresponding lesson's examples.

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And all scripts should
start with a doc string

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that states the purpose of that script.

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And since most of our scripts
are very straightforward,

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we typically just have
a one-line doc string;

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however, it's not uncommon
for a complex script

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or a library to have a very
detailed documentation string.

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Now we're going to be
working in this example

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with the list called numbers, which

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just contains five values.

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And we have a couple of print statements

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to get us started here.

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Let's take a look at the
second one for a moment

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because in this f string
we have a placeholder.

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And I just want you to reemphasize

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the fact that we have a
single quoted f string.

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And because of the fact
that we're outputting

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a string value in this placeholder

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we're wrapping that
string, that nested string,

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in double quote characters
that way we don't get an error

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because of nesting single quote characters

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within single quote characters.

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So that's why we have double
quote characters here.

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And you may recall that
this is not an emoji,

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but rather a format specifier indicating

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that we want to write a
line, the string value,

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in a field of eight characters.

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So what's going to happen here

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is we'll display the
literal characters' index,

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which is five character positions,

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and then in the next
eight character positions

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we'll display these five characters

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preceded by three spaces, and then

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we'll have a couple of
spaces and the word Bar.

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And that will help us produce
the three column heads,

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and we'll use some similar formatting

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down here in the for loop to
produce the three columns.

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Now let's talk about this for loop.

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So we just showed you that
the enumerate function

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can produce a sequence of
tuples consisting of each value

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in the sequence that you
give it as an argument,

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in this case the list numbers and

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the index for each of those values.

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And again the order within those tuples

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will be the index followed by the value.

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So because we're getting tuples
from the enumerate function

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we are able to unpack those tuples

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into the appropriate number of variables.

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In the case of enumerate
that will always be two.

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And so we have the index and the value,

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and we'd like to format the output.

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We're going to display the index

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right aligned in a field of five,

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which will right align
it under the word index,

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five characters long.

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Then in a field of eight,
right aligned we're

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going to display the value
of the variable value.

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Then we have a couple of spaces here,

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same number as up above.

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And underneath the word
bar, we are going to

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display the value of this
highlighted expression.

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Now we haven't done this previously

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and this is another one of those

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cool little python features.

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When you multiply a string by an integer

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it repeats the string
that number of times.

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So what we want in this example

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is a bar of asterisks that matches up

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with the value of each
individual list element.

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So if I say multiply the string
asterisk by the value 19,

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what I'm going to get is
19 consecutive asterisks

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as a string that is the value of

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this highlighted expression.

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Or if I multiply the
asterisk string by three

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I'll get a string of
three asterisks, etc. etc.

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So anytime you multiply
a sequence by an integer,

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you repeat that sequence the
specified number of times.

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And this little fore loop produced,

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going back over here,
these rows of the output.