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

abtin
page 20: … protoc command… I had to additionally run the following go get commands in order to be able to compile protobuf code using go...
New
jon
Some minor things in the paper edition that says “3 2020” on the title page verso, not mentioned in the book’s errata online: p. 186 But...
New
Alexandr
Hi everyone! There is an error on the page 71 in the book “Programming machine learning from coding to depp learning” P. Perrotta. You c...
New
JohnS
I can’t setup the Rails source code. This happens in a working directory containing multiple (postgres) Rails apps. With: ruby-3.0.0 s...
New
AufHe
I’m a newbie to Rails 7 and have hit an issue with the bin/Dev script mentioned on pages 112-113. Iteration A1 - Seeing the list of prod...
New
creminology
Skimming ahead, much of the following is explained in Chapter 3, but new readers (like me!) will hit a roadblock in Chapter 2 with their ...
New
mert
AWDWR 7, page 152, page 153: Hello everyone, I’m a little bit lost on the hotwire part. I didn’t fully understand it. On page 152 @rub...
New
New
davetron5000
Hello faithful readers! If you have tried to follow along in the book, you are asked to start up the dev environment via dx/build and ar...
New
dachristenson
I just bought this book to learn about Android development, and I’m already running into a major issue in Ch. 1, p. 20: “Update activity...
New

Other popular topics Top

PragmaticBookshelf
Ruby, Io, Prolog, Scala, Erlang, Clojure, Haskell. With Seven Languages in Seven Weeks, by Bruce A. Tate, you’ll go beyond the syntax—and...
New
dimitarvp
Small essay with thoughts on macOS vs. Linux: I know @Exadra37 is just waiting around the corner to scream at me “I TOLD YOU SO!!!” but I...
New
Exadra37
I am asking for any distro that only has the bare-bones to be able to get a shell in the server and then just install the packages as we ...
New
PragmaticBookshelf
Build highly interactive applications without ever leaving Elixir, the way the experts do. Let LiveView take care of performance, scalabi...
New
AstonJ
Was just curious to see if any were around, found this one: I got 51/100: Not sure if it was meant to buy I am sure at times the b...
New
hilfordjames
There appears to have been an update that has changed the terminology for what has previously been known as the Taskbar Overflow - this h...
New
sir.laksmana_wenk
I’m able to do the “artistic” part of game-development; character designing/modeling, music, environment modeling, etc. However, I don’t...
New
AstonJ
This is a very quick guide, you just need to: Download LM Studio: https://lmstudio.ai/ Click on search Type DeepSeek, then select the o...
New
Fl4m3Ph03n1x
Background Lately I am in a quest to find a good quality TTS ai generation tool to run locally in order to create audio for some videos I...
New
PragmaticBookshelf
Use advanced functional programming principles, practical Domain-Driven Design techniques, and production-ready Elixir code to build scal...
New

Sub Categories: