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

Distributed Services With Go - gogoproto on linux

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...

#errata /book-distributed-services-with-go

14 2953 7

2020-10-16 05:21:10 UTC

New

PragProg Customers

Web Development with Clojure, Third Edition: Issue adding Shadow CLJS

Title: Web Development with Clojure, Third Edition, pg 116 Hi - I just started chapter 5 and I am stuck on page 116 while trying to star...

#question /book-web-development-with-clojure-third-edition

4 1199 4

2021-01-10 05:30:17 UTC

New

PragProg Customers

Hands-on Rust: can_place logic is "inside out"

Title: Hands-On Rust (Chapter 11: prefab) Just played a couple of amulet-less games. With a bit of debugging, I believe that your can_p...

#errata /book-hands-on-rust

22 1628 20

2022-03-29 12:23:50 UTC

New

PragProg Customers

Programming Kotlin: Difference between SupervisorJob() and supervisorScope (324, 325)

Hi @venkats, It has been mentioned in the description of ‘Supervisory Job’ title that 2 things as mentioned below result in the same eff...

#question /book-programming-kotlin

0 2242 2

2021-03-16 11:28:51 UTC

New

PragProg Customers

Distributed Services with Go: receiving Unknown flag: --go_opt when compiling protobuf (page 20)

When trying to generate the protobuf .go file, I receive this error: Unknown flag: --go_opt libprotoc 3.12.3 MacOS 11.3.1 Googling ...

/book-distributed-services-with-go

0 4924 3

2021-08-18 18:19:51 UTC

New

PragProg Customers

Python Testing with pytest, Second Edition: File not Found Error (page 43)

I ran this command after installing the sample application: $ cards add do something --owner Brian And got a file not found error: Fil...

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

5 4391 7

2021-07-03 13:51:08 UTC

New

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

2024-12-18 18:02:25 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

Hands-on Rust: Chapter 3: Can't get first hello to run

Hello @herbert ! Trying to get the very first “Hello, Bracket Terminal!" example to run (p. 53). I develop on an Amazon EC2 instance runn...

#question /book-hands-on-rust

0 1147 2

2025-01-07 19:49:45 UTC

New

PragProg Customers

Machine Learning in Elixir:Error installing EXLA dependency - Page 25

Getting an error when installing the dependencies at the start of this chapter: could not compile dependency :exla, "mix compile" failed...

#errata /book-machine-learning-in-elixir

1 1159 10

2025-01-03 12:05:01 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

1050 21151 394

2026-01-01 02:02:13 UTC

New

Linux>Questions

AMD or Intel for Programming with Linux as the OS?

I am thinking in building or buy a desktop computer for programing, both professionally and on my free time, and my choice of OS is Linux...

#mobile #android #web-development #linux #desktop-computer #mobile-development

36 6006 10

2020-07-12 20:50:05 UTC

New

General Dev>Hardware

Keyboard thock (sound)

I’ve been hearing quite a lot of comments relating to the sound of a keyboard, with one of the most desirable of these called ‘thock’, he...

/keyboards #mechanical-keyboards

14 11197 8

2020-11-11 11:59:23 UTC

New

Backend>Chat

Data Structures and Algorithms with Elixir

This is going to be a long an frequently posted thread. While talking to a friend of mine who has taken data structure and algorithm cou...

/elixir #algorithms #data-structures

108 11869 31

2024-11-14 02:14:00 UTC

New

AI>In The News

How to fix the eyes in AI-generated images

aidemos.info

0 4508 0

2022-09-10 13:54:33 UTC

New

General Dev>In The News

Jan: An open source alternative to ChatGPT that runs on the desktop

Jan | Rethink the Computer. Jan turns your computer into an AI machine by running LLMs locally on your computer. It’s a privacy-focus, l...

jan.ai

#desktop #chatgpt

4 5652 4

2024-03-29 08:42:30 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

Backend>Learning Resources

Ash Framework

Explore the power of Ash Framework by modeling and building the domain for a real-world web application. Rebecca Le @sevenseacat and ...

pragprog.com

#pragprog /elixir #published-book /ash /book-ash-framework

15 7555 9

2025-02-06 12:19:21 UTC

New

AI>Chat

Post your DeepSeek results

Curious what kind of results others are getting, I think actually prefer the 7B model to the 32B model, not only is it faster but the qua...

/deepseek

15 4275 15

2025-03-06 23:29:12 UTC

New

AI>Questions

What are the best text-to-speech ai generation tools that you can run locally?

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...

#ai #text-to-speech

6 8411 3

2025-03-24 16:48:39 UTC

New

Programming Machine Learning:

kai

Programming Machine Learning:

Most Liked

kai

Where Next?

Popular Pragmatic Bookshelf topics

Distributed Services With Go - gogoproto on linux

Web Development with Clojure, Third Edition: Issue adding Shadow CLJS

Hands-on Rust: can_place logic is "inside out"

Programming Kotlin: Difference between SupervisorJob() and supervisorScope (324, 325)

Distributed Services with Go: receiving Unknown flag: --go_opt when compiling protobuf (page 20)

Python Testing with pytest, Second Edition: File not Found Error (page 43)

Build a Weather Station with Elixir and Nerves: 'mix deps.get' does not work if user has not created a keyfile (page 16)

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

Hands-on Rust: Chapter 3: Can't get first hello to run

Machine Learning in Elixir:Error installing EXLA dependency - Page 25

Other popular topics

What dev-related stuff have you been up to?