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

The Pragmatic Programmer, 20th Anniversary Edition errata

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...

#errata /book-the-pragmatic-programmer-20th-anniversary-edition

10 2636 9

2024-09-02 13:34:40 UTC

New

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

2020-07-05 23:04:12 UTC

New

PragProg Customers

The Ray Tracer Challenge: various errata

The following is cross-posted from the original Ray Tracer Challenge forum, from a post by garfieldnate. I’m cross-posting it so that the...

#errata /book-the-ray-tracer-challenge

4 2434 3

2021-05-25 09:44:21 UTC

New

PragProg Customers

Programming Phoenix LiveView: B03 (page 56-57) auth exercise

Dear Sophie. I tried to do the “Authorization” exercise and have two questions: When trying to plug in an email-service, I found the ...

#question /book-programming-phoenix-liveview

1 1181 3

2021-05-04 15:14:02 UTC

New

PragProg Customers

Build a Weather Station with Elixir and Nerves: SGP30 vs SGP40

This is as much a suggestion as a question, as a note for others. Locally the SGP30 wasn’t available, so I ordered a SGP40. On page 53, ...

#suggestion /book-build-a-weather-station-with-elixir-and-nerves

0 1292 2

2024-03-20 19:56:42 UTC

New

PragProg Customers

Kotlin and Android Development featuring Jetpack: android:tint vs app:tint (chapter 7, p186)

I found an issue in Chapter 7 regarding android:backgroundTint vs app:backgroundTint. How to replicate: load chapter-7 from zipfile i...

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

0 3566 3

2022-04-26 09:10:52 UTC

New

PragProg Customers

Programming Phoenix LiveView: book not updated to version 1.6 (p. 18)

In general, the book isn’t yet updated for Phoenix version 1.6. On page 18 of the book, the authors indicate that an auto generated of ro...

#errata /book-programming-phoenix-liveview

9 2051 12

2022-02-08 11:31:40 UTC

New

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

2022-01-24 15:18:41 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

Agile Web Development with Rails 7: Example code does not work delete method (page 78)

On page 78 the following code appears: <%= link_to ‘Destroy’, product, class: ‘hover:underline’, method: :delete, data: { confirm...

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

1 1266 2

2022-01-29 08:01:09 UTC

New

Other popular topics

Backend>Learning Resources

Testing Elixir

Write Elixir tests that you can be proud of. Dive into Elixir’s test philosophy and gain mastery over the terminology and concepts that u...

pragprog.com

#pragprog /elixir #published-book /book-testing-elixir

33 5004 8

2021-01-05 06:17:50 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

BIIP MT3 Extended 2048 Custom Keycap Set (Drop)

This looks like a stunning keycap set :orange_heart: A LEGENDARY KEYBOARD LIVES ON When you bought an Apple Macintosh computer in the e...

/keyboards #apple #keycaps #mechanical-keyboards

14 6713 7

2020-12-12 19:58:26 UTC

New

General Dev>Dev Chat

How fast do you type? Check your WPM here!

Do the test and post your score :nerd_face: :keyboard: If possible, please add info such as the keyboard you’re using, the layout (Qw...

typing-speed-test.aoeu.eu

/keyboards

82 7682 31

2021-07-10 05:52:20 UTC

New

macOS>Chat

My thoughts on macOS vs Linux

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...

#macos #linux

166 9730 69

2021-04-10 22:36:29 UTC

New

General Dev>Dev Chat

The V Programming Language

The V Programming Language Simple language for building maintainable programs V is already mentioned couple of times in the forum, but I...

#programminguages /v

21 13874 7

2021-04-12 15:13:42 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

Community>In The Spotlight

Spotlight: Rebecca Skinner (Author) Interview and AMA!

Author Spotlight Rebecca Skinner @RebeccaSkinner Welcome to our latest author spotlight, where we sit down with Rebecca Skinner, auth...

#author-spotlight /haskell /book-effective-haskell

106 11719 28

2022-11-16 10:29:37 UTC

New

General Dev>In The News

X can’t stop spread of explicit, fake AI Taylor Swift images

Will Swifties’ war on AI fakes spark a deepfake porn reckoning?

arstechnica.com

/swift

0 8379 0

2024-01-26 05:47:12 UTC

New

Backend>Learning Resources

Engineering Elixir Applications

Develop, deploy, and debug BEAM applications using BEAMOps: a new paradigm that focuses on scalability, fault tolerance, and owning each ...

pragprog.com

#pragprog /elixir #published-book /book-engineering-elixir-applications

40 7136 21

2024-11-08 15:13:02 UTC

New

Programming Machine Learning:

kai

Programming Machine Learning:

Most Liked

kai

Where Next?

Popular Pragmatic Bookshelf topics

The Pragmatic Programmer, 20th Anniversary Edition errata