mvellandi

mvellandi

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

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.

Marked As Solved

tonyhammond

tonyhammond

Author of Exploring Graphs with Elixir

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.

Where Next?

Popular Pragmatic Bookshelf topics Top

belgoros
Following the steps described in Chapter 6 of the book, I’m stuck with running the migration as described on page 84: bundle exec sequel...
New
ianwillie
Hello Brian, I have some problems with running the code in your book. I like the style of the book very much and I have learnt a lot as...
New
herminiotorres
Hi @Margaret , On page VII the book tells us the example and snippets will be all using Elixir version 1.11 But on page 3 almost the en...
New
AleksandrKudashkin
On the page xv there is an instruction to run bin/setup from the main folder. I downloaded the source code today (12/03/21) and can’t see...
New
AndyDavis3416
@noelrappin Running the webpack dev server, I receive the following warning: ERROR in tsconfig.json TS18003: No inputs were found in c...
New
nicoatridge
Hi, I have just acquired Michael Fazio’s “Kotlin and Android Development” to learn about game programming for Android. I have a game in p...
New
brunogirin
When I run the coverage example to report on missing lines, I get: pytest --cov=cards --report=term-missing ch7 ERROR: usage: pytest [op...
New
oaklandgit
Hi, I completed chapter 6 but am getting the following error when running: thread 'main' panicked at 'Failed to load texture: IoError(O...
New
akraut
The markup used to display the uploaded image results in a Phoenix.LiveView.HTMLTokenizer.ParseError error. lib/pento_web/live/product_l...
New
bjnord
Hello @herbert ! Trying to get the very first “Hello, Bracket Terminal!" example to run (p. 53). I develop on an Amazon EC2 instance runn...
New

Other popular topics Top

Devtalk
Reading something? Working on something? Planning something? Changing jobs even!? If you’re up for sharing, please let us know what you’...
1050 21151 394
New
PragmaticBookshelf
Learn from the award-winning programming series that inspired the Elixir language, and go on a step-by-step journey through the most impo...
New
AstonJ
We have a thread about the keyboards we have, but what about nice keyboards we come across that we want? If you have seen any that look n...
New
AstonJ
I have seen the keycaps I want - they are due for a group-buy this week but won’t be delivered until October next year!!! :rofl: The Ser...
New
AstonJ
This looks like a stunning keycap set :orange_heart: A LEGENDARY KEYBOARD LIVES ON When you bought an Apple Macintosh computer in the e...
New
Exadra37
Oh just spent so much time on this to discover now that RancherOS is in end of life but Rancher is refusing to mark the Github repo as su...
New
AstonJ
Continuing the discussion from Thinking about learning Crystal, let’s discuss - I was wondering which languages don’t GC - maybe we can c...
New
New
rustkas
Intensively researching Erlang books and additional resources on it, I have found that the topic of using Regular Expressions is either c...
New
NewsBot
Node.js v22.14.0 has been released. Link: Release 2025-02-11, Version 22.14.0 'Jod' (LTS), @aduh95 · nodejs/node · GitHub
New

Sub Categories: