kai

Programming Machine Learning:

Programming Machine Learning
From Coding to Deep Learning
German edition

Chapter 11
Training the network
Page 191

def back(X, Y, y_hat, w2, h):
w2_gradient = np.matmul(prepend_bias(h).T, y_hat - Y) / X.shape[0]

 a_gradient = np.matmul(y_hat - Y, w2[1:].T) * sigmoid_gradient(h)
 w1_gradient = np.matmul(prepend_bias(X).T, a_gradient) / X.shape[0]

 return (w1_gradient, w2_gradient)

Hi Paolo,
can you explain me how to come to the decision to multiply this expression:
np.matmul(y_hat - Y, w2[1:].T) * sigmoid_gradient(h)
element by element?

Sincerely,
Kai

4 comments

#question /book-programming-machine-learning

1 553 4

2023-10-03 20:36:18 UTC

Most Liked

kai

As I understand it, there is no recipe to derive compositions of functions, whose inputs are matrices, according to them, as it is the case with a scalar.

Thank you for giving me an answer that helped my understanding anyway.

I am fascinated by mathematics and its power. But to be able to see its beauty, it requires a lot of time. That is why I asked such a question.

Your book was recommended to me and declared very worthwhile, which I can confirm 100%. It is my introduction to ML. Thank you for it!

Translated with DeepL Translate: The world's most accurate translator (free version)

Post #5

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

question

Home PragProg Customers

#question /book-programming-machine-learning

1 553 4

Last post

Popular Pragmatic Bookshelf topics

PragProg Customers

Python Testing with pytest: pytest now requires markers to be declared (downloadable code)

Many tasks_proj/tests directories exist in chapters 2, 3, 5 that have tests that use the custom markers smoke and get, which are not decl...

#errata /book-python-testing-with-pytest

2 1383 2

2021-02-16 14:15:02 UTC

New

PragProg Customers

Build Websites with Hugo: Code will not run in a working Hugo setup

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...

#question /book-build-websites-with-hugo

0 1501 3

2021-01-29 18:54:24 UTC

New

PragProg Customers

The Cucumber for Java Book:

Hello! On page xix of the preface, it says there is a community forum "… for help if your’re stuck on one of the exercises in this book… ...

#question /book-the-cucumber-for-java-book

3 1143 1

2021-01-12 18:03:10 UTC

New

PragProg Customers

Python Testing with pytest, Second Edition: cards pip install error (page 12)

#book-python-testing-with-pytest-second-edition Hi. Thanks for writing the book. I am just learning so this might just of been an issue ...

#errata /book-python-testing-with-pytest-second-edition

4 1191 3

2021-07-03 13:40:39 UTC

New

PragProg Customers

Hands-on Rust: Adequate docs for bracket_lib

I’m new to Rust and am using this book to learn more as well as to feed my interest in game dev. I’ve just finished the flappy dragon exa...

#question /book-hands-on-rust

5 1516 3

2021-07-15 19:29:13 UTC

New

PragProg Customers

Kotlin and Android Development featuring Jetpack: $kotlin_version ? (page 8)

I’m running Android Studio “Arctic Fox” 2020.3.1 Patch 2, and I’m embarrassed to admit that I only made it to page 8 before running into ...

#errata /book-kotlin-and-android-development-featuring-jetpack

0 1698 3

2021-09-03 21:44:18 UTC

New

PragProg Customers

Powerful Command-Line Applications in Go: Exercise Solutions (many pages)

Is there any place where we can discuss the solutions to some of the exercises? I can figure most of them out, but am having trouble with...

#question /book-powerful-command-line-applications-in-go

17 1396 9

2022-02-09 15:00:31 UTC

New

PragProg Customers

Modern front-end development for Rails, second edition - Struggling to get the first chapter to work

After running /bin/setup, the first error was: The foreman' command exists in these Ruby versions: That was easy to fix: gem install fore...

#errata /book-modern-front-end-development-for-rails

1 1116 3

2023-06-22 14:09:32 UTC

New

PragProg Customers

Kotlin and Android Development featuring Jetpack: error concerning function getCurrentStandings in BaseballDao.java

@mfazio23 I’m following the indications of the book and arriver ad chapter 10, but the app cannot be compiled due to an error in the Bas...

#question /book-kotlin-and-android-development-featuring-jetpack

1 3397 6

2022-07-22 14:06:06 UTC

New

PragProg Customers

Kotlin and Android Development featuring Jetpack: End Ch. 11 app runs but consistently crashes

I’ve got to the end of Ch. 11, and the app runs, with all tabs displaying what they should – at first. After switching around between St...

#question /book-kotlin-and-android-development-featuring-jetpack

0 936 8

2024-01-05 05:43:55 UTC

New

Other popular topics

General Dev>Learning Resources

A Common-Sense Guide to Data Structures and Algorithms, Second Edition

Algorithms and data structures are much more than abstract concepts. Mastering them enables you to write code that runs faster and more e...

pragprog.com

#pragprog /python /ruby #published-book /book-a-common-sense-guide-to-data-structures-and-algorithms-second-edition #math #algorithms /js

19 6022 5

2020-08-14 00:58:37 UTC

New

General Dev>Hardware

What monitor(s) do you have for programming?

Please tell us what is your preferred monitor setup for programming(not gaming) and why you have chosen it. Does your monitor have eye p...

#monitors #coding #programming #development

227 11362 88

2022-02-01 12:02:08 UTC

New

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

2023-07-27 16:30:57 UTC

New

General Dev>Code Editors

Dendron: a personal knowledge management tool on top of VSCode

/vscode #visual-studio-code

30 7372 9

2021-05-05 12:15:29 UTC

New

General Dev>Hardware

Planck vs Preonic vs Subatomic (Keyboards)

I ended up cancelling my Moonlander order as I think it’s just going to be a bit too bulky for me. I think the Planck and the Preonic (o...

/keyboards #mechanical-keyboards #ortholinear #planck #preonic

105 17596 47

2021-05-28 21:32:35 UTC

New

Linux>Questions

What is the most minimalist Linux server distro?

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 ...

#linux #servers

66 25846 24

2022-04-13 13:30:03 UTC

New

Backend>Chat

How to install Ruby 3 with ASDF

In case anyone else is wondering why Ruby 3 doesn’t show when you do asdf list-all ruby :man_facepalming: do this first: asdf plugin-upd...

/ruby #asdf

11 5961 4

2021-02-02 08:02:13 UTC

New

Backend>Learning Resources

Concurrent Data Processing in Elixir

Learn different ways of writing concurrent code in Elixir and increase your application's performance, without sacrificing scalability or...

pragprog.com

#pragprog /elixir #published-book /book-concurrent-data-processing-in-elixir

78 6059 24

2021-09-04 12:35:42 UTC

New

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

2021-11-10 20:03:09 UTC

New

Backend>Learning Resources

Simplicity

Fight complexity and reclaim the original spirit of agility by learning to simplify how you develop software. The result: a more humane a...

pragprog.com

#pragprog #published-book /book-simplicity

10 6553 8

2025-03-14 21:53:12 UTC

New

Programming Machine Learning:

kai

Programming Machine Learning:

Most Liked

kai

Where Next?

Popular Pragmatic Bookshelf topics

Python Testing with pytest: pytest now requires markers to be declared (downloadable code)