Fixed typo (#1397)

* Fixed typo

There seems to be a typo in the list names, and in the associated figures

* Update screenshots

* Now with the little icons

---------

Co-authored-by: mine-cetinkaya-rundel <cetinkaya.mine@gmail.com>

rectangling.qmd

@@ -87,7 +87,7 @@ str(x5)
 ```
 
 As lists get even larger and more complex, `str()` eventually starts to fail, and you'll need to switch to `View()`[^rectangling-1].
-@fig-view-collapsed shows the result of calling `View(x4)`. The viewer starts by showing just the top level of the list, but you can interactively expand any of the components to see more, as in @fig-view-expand-1. RStudio will also show you the code you need to access that element, as in @fig-view-expand-2. We'll come back to how this code works in @sec-subset-one.
+@fig-view-collapsed shows the result of calling `View(x5)`. The viewer starts by showing just the top level of the list, but you can interactively expand any of the components to see more, as in @fig-view-expand-1. RStudio will also show you the code you need to access that element, as in @fig-view-expand-2. We'll come back to how this code works in @sec-subset-one.
 
 [^rectangling-1]: This is an RStudio feature.
 
@@ -98,7 +98,7 @@ As lists get even larger and more complex, `str()` eventually starts to fail, an
 #|   The viewer opens showing only the top level of the list.
 #| fig.alt: >
 #|   A screenshot of RStudio showing the list-viewer. It shows the
-#|   two children of x4: the first child is a double vector and the
+#|   two children of x5: the first child is a double vector and the
 #|   second child is a list. A rightward facing triable indicates that the
 #|   second child itself has children but you can't see them.
 #| echo: false
@@ -113,7 +113,7 @@ knitr::include_graphics("screenshots/View-1.png", dpi = 220)
 #|   of the list so that you can also see its children.
 #| fig.alt: >
 #|   Another screenshot of the list-viewer having expand the second
-#|   child of x2. It also has two children, a double vector and another
+#|   child of x5. It also has two children, a double vector and another
 #|   list.
 #| echo: false
 #| out-width: NULL
@@ -126,9 +126,9 @@ knitr::include_graphics("screenshots/View-2.png", dpi = 220)
 #|   You can repeat this operation as many times as needed to get to the 
 #|   data you're interested in. Note the bottom-left corner: if you click
 #|   an element of the list, RStudio will give you the subsetting code
-#|   needed to access it, in this case `x4[[2]][[2]][[2]]`.
+#|   needed to access it, in this case `x5[[2]][[2]][[2]]`.
 #| fig.alt: >
-#|   Another screenshot, having expanded the grandchild of x4 to see its
+#|   Another screenshot, having expanded the grandchild of x5 to see its
 #|   two children, again a double vector and a list.
 #| echo: false
 #| out-width: NULL