Book updates

Author: Susan Vanderplas

_freeze/part-gen-prog/02-prog-functions/execute-results/html.json

@@ -384,8 +384,38 @@ not(False) or not(False)
 **Functions** are sets of instructions that take **arguments** and **return** values.
 Strictly speaking, mathematical operators (like those above) are a special type of functions -- but we aren't going to get into that now.
 
+::: callout-info
+### Function Vocabulary
+
+Suppose I have a function called `add(x, y)` which takes two numbers and adds them together.
+
+In this example, `add` is the function name, and `x` and `y` are **parameters**: placeholder names for information to be passed into the function.
+Not all functions have named parameters, but it is common for named parameters to provide some indication of what information is supposed to go in that spot.
+
+When I call the function -- that is, I use it to add two numbers together, I have to pass in **arguments**.
+Arguments are values which are assigned to parameters in the function and affect the result. 
+This is pretty technical and a bit nit-picky, but it's good to see information multiple times - we'll revisit functions in @sec-functions. 
+
+The **function call** would be `add(x = 3, y = 2)`, where 3 and 2 are the arguments.
+The function call would be evaluated and would **return** 5 as the answer (assuming that `add` does what it says it does). 
+
+
+Let's see these words in a more concrete setting. 
+
+![Small excerpt from the R reference card, showing the `which.max` and `which.min` functions](../images/gen-prog/function-vocab.png){fig-alt="An image which has the heading 'Data selection and manipulation', and below that has the text 'which.max(x) returns the index of the greatest element of x' and 'which.min(x) returns the index of the smallest element of x'."}
+
+- `which.max` and `which.min` are the function names
+- `x` is the parameter
+
+When I type `which.max(x = c(2:10))` into the R console and hit Enter, 
+- `c(2:10) = c(2, 3, 4, 5, 6, 7, 8, 9, 10)` is the argument
+- inside `which.max`, this argument has the name `x` (mostly helpful for debugging)
+- `which.max` will return 9, which is the index of `x` with the largest value (10)
+
+:::
+
 We're also not going to talk about how to create our own functions just yet.
-Instead, I'm going to show you how to *use* functions.
+Instead, in this chapter, let's figure out how to *use* functions.
 
 ::: callout-warning
 ### Cheat Sheets!
@@ -399,7 +429,7 @@ It may be helpful at this point to print out the [R reference card](../files/Sho
 
 [^02-prog-functions-2]: From http://sixthresearcher.com/wp-content/uploads/2016/12/Python3_reference_cheat_sheet.pdf
 
-**Methods** are a special type of function that operate on a specific variable type.
+**Methods** are a special type of function that operate on a specific data type.
 In Python, methods are applied using the syntax `variable.method_name()`.
 So, you can get the length of a string variable `my_string` using `my_string.length()`.
 

_freeze/part-gen-prog/02-prog-functions/figure-html/unnamed-chunk-41-1.png

@@ -245,6 +245,8 @@ To create a repository, you can start with your local computer first, or you can
 Both methods are relatively simple, but the options you choose depend on which method you're using, so be careful not to get them confused. 
 :::
 
+::: panel-tabset
+
 #### Local repository first
 
 Let's suppose you already have a folder on your machine named `hello-world-1` (you may want to create this folder now). You've created a starter document, say, a text file named README with "hello world" written in it. 
@@ -340,6 +342,8 @@ Command line method:
 <iframe width="1048" height="590" src="https://www.youtube.com/embed/y4cpJ_VaRMg" title="Create the github repository first, using the command line to work with git" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
 :::
 
+:::
+
 ### Adding files
 
 `git add` tells git that you want it to track a particular file.