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

Apple Game Frameworks and Technologies: Screen image may be wrong (p 13)

Working through the steps (checking that the Info,plist matches exactly), run the demo game and what appears is grey but does not fill th...

#errata /book-apple-game-frameworks-and-technologies

11 1081 5

2021-05-15 17:31:07 UTC

New

PragProg Customers

Programming Flutter: Image.toByteData() does not exist (page40)

your book suggests to use Image.toByteData() to convert image to bytes, however I get the following error: "the getter ‘toByteData’ isn’t...

/book-programming-flutter #question

1 4102 2

2021-02-23 16:03:08 UTC

New

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

2022-08-28 01:56:06 UTC

New

PragProg Customers

Python Testing with pytest, Second Edition: unrecognized arguments error (page 122)

When I run the coverage example to report on missing lines, I get: pytest --cov=cards --report=term-missing ch7 ERROR: usage: pytest [op...

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

0 4000 1

2021-12-03 05:36:38 UTC

New

PragProg Customers

Python Testing with pytest, Second Edition:Abou epub format

Is the book’s epub format available to read on Google Play Books?

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

0 1126 3

2022-01-20 20:47:42 UTC

New

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

2022-02-28 15:41:06 UTC

New

PragProg Customers

Agile Web Development with Rails 7: (page 70)

Title: Agile Web Development with Rails 7: (page 70) I am running windows 11 pro with rails 7.0.3 and ruby 3.1.2p20 (2022-04-12 revision...

#question /book-agile-web-development-with-rails-7

0 1129 1

2022-06-08 13:17:16 UTC

New

PragProg Customers

The Definitive ANTLR 4 Reference - "Java.g4" grammer (used on page 40) no longer passes ANTLR

@parrt In the context of Chapter 4.3, the grammar Java.g4, meant to parse Java 6 compilation units, no longer passes ANTLR (currently 4....

#errata /book-the-definitive-antlr-4-reference

0 1020 3

2023-02-14 01:34:49 UTC

New

PragProg Customers

Kotlin and Android Development featuring Jetpack: Unique constraint error when running chapter 5 code changes

@mfazio23 I’ve applied the changes from Chapter 5 of the book and everything builds correctly and runs. But, when I try to start a game,...

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

0 1180 10

2023-08-07 20:43:16 UTC

New

Other popular topics

General Dev>Dev Chat

What dev-related stuff have you been up to?

Reading something? Working on something? Planning something? Changing jobs even!? If you’re up for sharing, please let us know what you’...

#community

1052 21915 398

2026-02-18 06:51:11 UTC

New

Backend>Learning Resources

Distributed Services with Go

Take your Go skills to the next level by learning how to design, develop, and deploy a distributed service. Start from the bare essential...

pragprog.com

#pragprog /go #published-book /book-distributed-services-with-go

1 4310 0

2020-04-14 19:05:22 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>Learning Resources

Python Testing with pytest, Second Edition

Create efficient, elegant software tests in pytest, Python's most powerful testing framework. Brian Okken @brianokken Edited by Kat...

pragprog.com

#pragprog /python #published-book /book-python-testing-with-pytest-second-edition

16 7461 4

2021-06-25 16:57:39 UTC

New

Data Science

Can AI/ML predict a lottery win?

Biggest jackpot ever apparently! :upside_down_face: I don’t (usually) gamble/play the lottery, but working on a program to predict the...

#ai #machine-learning

19 3939 10

2021-10-18 19:01:41 UTC

New

Community>In The Spotlight

Spotlight: Dmitry Zinoviev (Author) Interview and AMA!

Author Spotlight Dmitry Zinoviev @aqsaqal Today we’re putting our spotlight on Dmitry Zinoviev, author of Data Science Essentials in ...

#author-spotlight /python /book-complex-network-analysis-in-python /book-data-science-essentials-in-python /book-resourceful-code-reuse /book-pythonic-programming

33 5211 14

2022-10-11 20:07:10 UTC

New

Community>In The Spotlight

Spotlight: Jamis Buck (Author) Interview and AMA!

Author Spotlight Jamis Buck @jamis This month, we have the pleasure of spotlighting author Jamis Buck, who has written Mazes for Prog...

#author-spotlight /ruby /book-the-ray-tracer-challenge /book-mazes-for-programmers

21 6352 9

2022-09-28 18:21:15 UTC

New

Backend>Learning Resources

Programming Ruby 3.2 (5th Edition)

Programming Ruby is the most complete book on Ruby, covering both the language itself and the standard library as well as commonly used t...

twitter.com

#pragprog /ruby /rails #published-book /book-programming-ruby-3-2-5th-edition

28 8550 13

2024-11-17 04:34:14 UTC

New

Android>Questions

Unresolved Reference to android in build.gradle.kts – Beginner Issue

Hello, I’m a beginner in Android development and I’m facing an issue with my project setup. In my build.gradle.kts file, I have the foll...

#binding

0 7460 2

2024-12-09 21:07:33 UTC

New

Backend>Learning Resources

MySQL 9 Essentials

A concise guide to MySQL 9 database administration, covering fundamental concepts, techniques, and best practices. Neil Smyth MySQL...

pragprog.com

#pragprog #published-book /mysql /book-mysql-9-essentials

2 4162 0

2025-03-12 13:05:49 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)

Apple Game Frameworks and Technologies: Screen image may be wrong (p 13)

Programming Flutter: Image.toByteData() does not exist (page40)

Kotlin and Android Development: Could not get unknown property ‘kotlin_version’…

Python Testing with pytest, Second Edition: unrecognized arguments error (page 122)

Python Testing with pytest, Second Edition:Abou epub format

Real-Time Phoenix: use PubSub with implementation of Phoenix.Socket.Transport rather than channels (page 37)

Agile Web Development with Rails 7: (page 70)

The Definitive ANTLR 4 Reference - "Java.g4" grammer (used on page 40) no longer passes ANTLR

Kotlin and Android Development featuring Jetpack: Unique constraint error when running chapter 5 code changes

Other popular topics