PragProg Customers

Programming Machine Learning: matplotlib broadcast error on page 58

tihnessa

tihnessa

Programming Machine Learning: matplotlib broadcast error on page 58

When I try to run the code multiple_regression_without_bias.py from page 58 of the book, I get the following error:

File “[path snipped]/multilple_regression_without_bias.py”, line 13, in gradient
return 2 * np.matmul(X.T * (predict(X, w) - Y)) / X.shape[0]
ValueError: operands could not be broadcast together with shapes (3,30) (30,1)

This happens whether I run the code I’ve typed in or the code I’ve downloaded from the PragProg website.

For information, my versions are:
Python 3.9.7
Numpy 1.26.3

Any help or advice would be greatly appreciated.

1 comment
/book-programming-machine-learning
0 217 1

First Post!

nusco

nusco

Author of Metaprogramming Ruby & Programming Machine Learning

Hello, @tihnessa! Sorry for the slow reply. I was on travel.

Somehow, the code you’re using isn’t the same as in the current book and downloadable code. It’s not:

return 2 * np.matmul(X.T * (predict(X, w) - Y)) / X.shape[0]

but rather:

return 2 * np.matmul(X.T, (predict(X, w) - Y)) / X.shape[0]

(Note the comma after X.T, as opposed to the multiplication).

I have no idea what happened here. Maybe this was a bug in the book that I later fixed, and you have an older version of the book+code? Or maybe you were experimenting with the code and changed that line? In any case, that seems to be the issue.

Can you please confirm that you got it fixed?

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
0 217 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
AleksandrKudashkin
PragProg Customers

Modern Front-End Development for Rails: B7 no main folder in the source code (page xv)
On the page xv there is an instruction to run bin/setup from the main folder. I downloaded the source code today (12/03/21) and can’t see...
#errata/book-modern-front-end-development-for-rails
2 1452 11
New
Chrichton
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
New
patoncrispy
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
New
fynn
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
New
brunogirin
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
New
hazardco
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
New
taguniversalmachine
PragProg Customers

Programming Phoenix LiveView: B6.0 pg 56 - current-user not set
It seems the second code snippet is missing the code to set the current_user: current_user: Accounts.get_user_by_session_token(session["...
#errata/book-programming-phoenix-liveview
0 1898 8
New
Henrai
PragProg Customers

The Ray Tracer Challenge: Cannot get rid of acne When implement Shadows in Chapter 8.
Hi, I’m working on the Chapter 8 of the book. After I add add the point_offset, I’m still able to see acne: In the image above, I re...
#question/book-the-ray-tracer-challenge
1 1052 4
New
redconfetti
PragProg Customers

Docker for Rails Developers - 'docker-machine' command deprecated (page 156)
Docker-Machine became part of the Docker Toolbox, which was deprecated in 2020, long after Docker Desktop supported Docker Engine nativel...
/book-docker-for-rails-developers#suggestion
0 896 0
New

Other popular topics Top

PragmaticBookshelf
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
New
AstonJ
Science/Tech>Tech Chat

What are you watching?
Or looking forward to? :nerd_face:
#community
498 14002 274
New
AstonJ
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
New
foxtrottwist
General Dev>Dev Chat

Warp—The blazingly fast, Rust-based terminal
A few weeks ago I started using Warp a terminal written in rust. Though in it’s current state of development there are a few caveats (tab...
/rust#terminal
52 6785 22
New
AstonJ
Science/Tech>Health & Diet

David Sinclair's new Lifespan podcast
We’ve talked about his book briefly here but it is quickly becoming obsolete - so he’s decided to create a series of 7 podcasts, the firs...
#health#podcasts#bio-hackers#david-sinclair
87 6790 49
New
AstonJ
General Dev>Code Editors

Doom-Emacs: Can't find emacs in your PATH
If you get Can't find emacs in your PATH when trying to install Doom Emacs on your Mac you… just… need to install Emacs first! :lol: bre...
#macos/emacs#doom-emacs
4 5837 0
New
PragmaticBookshelf
Backend>Learning Resources

Agile Web Development with Rails 8
Get the comprehensive, insider information you need for Rails 8 with the new edition of this award-winning classic. Sam Ruby @rubys ...
pragprog.com
#pragprog#web-development/ruby/rails#published-book/book-agile-web-development-with-rails-8
12 7404 7
New
AnfaengerAlex
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
New
AstonJ
AI>In The News

DeepSeek (671B) running on a cluster of 8 Mac Mini Pros with 64GB RAM each
This is cool! DEEPSEEK-V3 ON M4 MAC: BLAZING FAST INFERENCE ON APPLE SILICON We just witnessed something incredible: the largest open-s...
#ai#macs/deepseek
0 6695 1
New
RobertRichards
Game Dev>Chat

Hair Salon Games for Girls Fun
Hair Salon Games for Girls Fun Girls Hair Saloon game is mainly developed for kids. This game allows users to select virtual avatars to ...
#ios#android#unity#fun
2 3556 1
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!"

Linux New Media

Publishing Linux Magazine, ADMIN, and MakerSpace for 25+ years.

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!"

Linux New Media

Publishing Linux Magazine, ADMIN, and MakerSpace for 25+ years.

View all our sponsors ❯

We're in Beta

About us Mission Statement See our Roadmap