Exploring Graphs with Elixir: Missing directories (p 100, 105)

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Exploring Graphs with Elixir by @tonyhammond

p.100 – Ch 3 > Storing Graphs in the Graph Store > Listing
shows

“iex>​​ ​​list_graphs​
​ 	[..., "default.dot", "IMAGES", ...]”

but (to my recollection) we have not defined this directory yet, either manually or automatically through the shell command in:
p.68 – Ch 2 > Building a Graph Store > Creating a Storage area

I see a reference to this “images” directory later, as a module attribute in NativeGraph.Format
So I manually created it.

Then in
p.105 – Ch 3 > Visualizing Graphs > Rendering with Graph Viz
while creating the water molecule graph, we’re given:

“iex>​​ ​​with​​ ​​{:ok,​​ ​​dot}​​ ​​=​​ ​​Graph.to_dot(g)​​ ​​do​
​ 	​...>​​ ​​write_graph(dot,​​ ​​"dot/h2o.dot"​​)​
​ 	​...>​​ ​​end”

When trying this, I get a File error since the “dot” directory is unavailable. Not sure what I’m missing here, or if the directory is supposed to be automatically created?
I manually created a “dot” directory to make the code work as shown and tested in later pages.

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Yes, this was not very clear. These directories are to be added manually.

I added this text on p. 29 in Chapter 2, Building a Graph Store, section Listing:

“And we’ll also want to be able to access graphs and queries within any directories that we may add manually to our store.”

And on p. 47 in Chapter 3. Managing Graphs Natively with Elixir:

“In this case we have manually added an images/ directory.”

And on p. 49:
“And for better graph management note that we’ve manually added the dot/ and images/ directories in our graph store:”

Also I hadn’t been consistent in writing dot files to the dot/ directory. Fixed that too.