adding subsections

Author: nicole-a-moore

posts/2025-07-06-CSEE-intro-shiny/index.qmd

@@ -51,6 +51,8 @@ class(data)
 
 As you can see, the data are stored in a **list** object. 
 
+## Lists
+
 In R lists act as containers. Unlike atomic vectors, the contents of a list are not restricted to a single mode and can encompass any mixture of data types. Lists are sometimes called generic vectors, because the elements of a list can by of any type of R object, even lists containing further lists. This property makes them fundamentally different from atomic vectors.
 
 A list is a special type of vector. Each element can be a different type.
@@ -190,6 +192,8 @@ library(package)
   
 ```
 
+## Writing functions
+
 If we only had one university's network to plot, we could stop here... but we have 24 others to plot. Let's wrap our code in a **function** so that we can repeat several operations with a single command. 
 
 You can write your own functions in order to make repetitive operations using a single command. Let’s start by defining our function ```plot_network``` and the input parameter(s) that the user will feed to the function. Afterwards you will define the operation that you desire to program in the body of the function within curly braces ```{ }```. Finally, you need to assign the result (or output) of your function in the ```return()``` statement.