PragProg Customers

Programming Machine Learning - Dimension numbers correct? (page 118)

mscdit

mscdit

Programming Machine Learning - Dimension numbers correct? (page 118)

Hi @nusco,

I have a question regarding the dimension numbers of the matrices shown in the picture on page 118. What I am currently struggling with is, node “h_0” is used for bias purpose (which means constant value 1). So if weight vector w_1 has 201 columns, this implies that all hidden nodes h_0, h_1, … h_200 are calculated via w_1 … but looking in the code-snipets on page 122,

h = sigmoid(np.matmul(prepend_bias(X), w1))

vector h should have 202 entries, if w1 has 201, which doesn’t fit into the picture of page 118, or?

Thanks a lot,
Mscdit

1 comment
/book-programming-machine-learning
1 250 1

First Post!

nusco

nusco

Author of Metaprogramming Ruby & Programming Machine Learning

Here I am, at long last! Sorry for the slow reply, @mscdit . I was knocked out by the flu.

This looks indeed like a mistake in that diagram (that is even repeated in two consecutive chapters). w1 should be (785, 200), not (785, 201). Then the hidden layer is (M, 200), and it becomes (M, 201) when you prepend the biases.

Thank you for spotting it! I’ll add to the errata for future editions.

Post #2

Where Next?

View thread on forum
View Programming Machine Learning's book portal
Post errata for this book
Post a suggestion for this book
Post a question about this book
Post a review about this book
Home PragProg Customers
/book-programming-machine-learning
1 250 1
Last post

Popular Pragmatic Bookshelf topics Top

duke_meister
PragProg Customers

The Ray Tracer Challenge - where are the errata?
As per the title, thanks.
/book-the-ray-tracer-challenge
6 1681 4
New
iPaul
PragProg Customers

The Definitive ANTLR 4 Reference: Program deprecation warning
page 37 ANTLRInputStream input = new ANTLRInputStream(is); as of ANTLR 4 .8 should be: CharStream stream = CharStreams.fromStream(i...
#errata/book-the-definitive-antlr-4-reference
4 987 0
New
simonpeter
PragProg Customers

Web Development with Clojure, Third Edition: (create-migration "guestbook") not working (page 9)
When I try the command to create a pair of migration files I get an error. user=> (create-migration "guestbook") Execution error (Ill...
#errata/book-web-development-with-clojure-third-edition
5 1788 4
New
curtosis
PragProg Customers

Build a Weather Station with Elixir and Nerves: 'mix deps.get' does not work if user has not created a keyfile (page 16)
Running mix deps.get in the sensor_hub directory fails with the following error: ** (Mix) No SSH public keys found in ~/.ssh. An ssh aut...
#errata/book-build-a-weather-station-with-elixir-and-nerves
2 1457 3
New
nicoatridge
PragProg Customers

Kotlin and Android Development: Could not get unknown property ‘kotlin_version’…
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...
/book-kotlin-and-android-development-featuring-jetpack
0 8095 6
New
brunogirin
PragProg Customers

Python Testing with pytest, Second Edition: InterpreterNotFound error when running tox (page 150)
When running tox for the first time, I got the following error: ERROR: InterpreterNotFound: python3.10 I realised that I was running ...
#errata/book-python-testing-with-pytest-second-edition
0 1306 1
New
dsmith42
PragProg Customers

iOS Unit Testing by Example: 54 Don't seem to be getting the print out on tests (Xcode 13.2)
Hey there, I’m enjoying this book and have learned a few things alredayd. However, in Chapter 4 I believe we are meant to see the “>...
#question/book-ios-unit-testing-by-example
0 1963 3
New
rainforest
PragProg Customers

Real-Time Phoenix: use PubSub with implementation of Phoenix.Socket.Transport rather than channels (page 37)
Hi, I’ve got a question about the implementation of PubSub when using a Phoenix.Socket.Transport behaviour rather than channels. Before ...
#question/book-real-time-phoenix#websockets#phoenixsocket#pubsub
0 1528 3
New
Keton
PragProg Customers

Hands-on Rust: How do I debug a call chain in Rust?
When running the program in chapter 8, “Implementing Combat”, the printout Health before attack was never printed so I assumed something ...
#question/book-hands-on-rust
2 1034 2
New
davetron5000
PragProg Customers

Bug with dx/build - how to workaround until fix is up
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...
#errata/book-ruby-on-rails-background-jobs-with-sidekiq
3 1178 19
New

Other popular topics Top

AstonJ
General Dev>Dev Chat

What are you listening to?
A thread that every forum needs! Simply post a link to a track on YouTube (or SoundCloud or Vimeo amongst others!) on a separate line an...
#community#music
202 5126 102
New
AstonJ
General Dev>Dev Chat

Best chairs for developers?
What chair do you have while working… and why? Is there a ‘best’ type of chair or working position for developers?
#workspace#opinions
74 5463 41
New
AstonJ
General Dev>Code Editors

SpaceVim vs SpaceMacs
SpaceVim seems to be gaining in features and popularity and I just wondered how it compares with SpaceMacs in 2020 - anyone have any thou...
/vim#spacevim#spacemacs/emacs#code-editors
30 4336 14
New
brentjanderson
General Dev>Hardware

Moonlander Keyboard (Mechanical) (Ergonomic) (Split) (Ortholinear)
Bought the Moonlander mechanical keyboard. Cherry Brown MX switches. Arms and wrists have been hurting enough that it’s time I did someth...
#hardware/keyboards#moonlander#mechanical-keyboards#ortholinear#ergonomic
212 17779 90
New
DevotionGeo
Backend>Questions

Can someone explain the -t option/flag in docker run command?
I know that -t flag is used along with -i flag for getting an interactive shell. But I cannot digest what the man page for docker run com...
#docker
7 10261 2
New
AstonJ
General Dev>Hardware

Custom keyboard keycaps
There’s a whole world of custom keycaps out there that I didn’t know existed! Check out all of our Keycaps threads here: https://forum....
#hardware/keyboards#keycaps#mechanical-keyboards
15 11086 19
New
Maartz
General Dev>Dev Chat

Roc Language - a new purely functional programming language built for speed and ergonomics
Hi folks, I don’t know if I saw this here but, here’s a new programming language, called Roc Reminds me a bit of Elm and thus Haskell. ...
#programminguages#functional-programming
49 5164 14
New
AstonJ
Frontend>Chat

Online Hand to eye coordination test
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...
#online-tools
4 4562 1
New
First poster: CommunityNews
AI>In The News

How to fix the eyes in AI-generated images
aidemos.info
0 4508 0
New
PragmaticBookshelf
Community>In The Spotlight

Spotlight: VM Brasseur (Author) Interview and AMA!
Author Spotlight: VM Brasseur @vmbrasseur We have a treat for you today! We turn the spotlight onto Open Source as we sit down with V...
#author-spotlight/book-forge-your-future-with-open-source
16 5051 11
New
Back to top

Latest in Programming Machine Learning

Programming Machine Learning Portal ❯

PragProg Customers

Pragmatic Bookshelf PragProg Customers ❯

Latest on Devtalk

Devtalk ❯

We ❤️ helpful members!

We reward our most helpful members via our MOTM scheme - by giving away a whopping 25 books per year!

Member of the Month

Devtalk Sponsors

Pragmatic Bookshelf

Practical resources that improve the lives of professional developers.

Erlang Solutions

We build trusted fault-tolerant systems that scale to billions of users.

Honeybadger

Real-time error tracking, performance insights, and observability for devs.

EEF

Supporting innovation across the BEAM ecosystem.

coders51

We build reliable cloud platforms for business-critical systems.

Manning Publications

Develop your skills with books, videos, and courses.

AppSignal

Catch errors, track performance, monitor hosts and more.

WyeWorks

Enabling companies to succeed by building software people love.

Pragmatic Studio

Courses that move you from confusion to "Aha, now I get it!"

View all our sponsors ❯

Categories:

Sub Categories:

Popular Portals

Devtalk Sponsors

Pragmatic Bookshelf

Practical resources that improve the lives of professional developers.

Erlang Solutions

We build trusted fault-tolerant systems that scale to billions of users.

Honeybadger

Real-time error tracking, performance insights, and observability for devs.

EEF

Supporting innovation across the BEAM ecosystem.

coders51

We build reliable cloud platforms for business-critical systems.

Manning Publications

Develop your skills with books, videos, and courses.

AppSignal

Catch errors, track performance, monitor hosts and more.

WyeWorks

Enabling companies to succeed by building software people love.

Pragmatic Studio

Courses that move you from confusion to "Aha, now I get it!"

View all our sponsors ❯

We're in Beta

About us Mission Statement See our Roadmap