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.

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?

Where Next?

Popular Pragmatic Bookshelf topics Top

jon
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...
New
telemachus
Python Testing With Pytest - Chapter 2, warnings for “unregistered custom marks” While running the smoke tests in Chapter 2, I get these...
New
yulkin
your book suggests to use Image.toByteData() to convert image to bytes, however I get the following error: "the getter ‘toByteData’ isn’t...
New
mikecargal
Title: Hands-on Rust: question about get_component (page 295) (feel free to respond. “You dug you’re own hole… good luck”) I have somet...
New
Mmm
Hi, build fails on: bracket-lib = “~0.8.1” when running on Mac Mini M1 Rust version 1.5.0: Compiling winit v0.22.2 error[E0308]: mi...
New
HarryDeveloper
Hi @venkats, It has been mentioned in the description of ‘Supervisory Job’ title that 2 things as mentioned below result in the same eff...
New
swlaschin
The book has the same “Problem space/Solution space” diagram on page 18 as is on page 17. The correct Problem/Solution space diagrams ar...
New
brian-m-ops
#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 ...
New
leonW
I ran this command after installing the sample application: $ cards add do something --owner Brian And got a file not found error: Fil...
New
dsmith42
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 “>...
New

Other popular topics Top

AstonJ
If it’s a mechanical keyboard, which switches do you have? Would you recommend it? Why? What will your next keyboard be? Pics always w...
New
AstonJ
Or looking forward to? :nerd_face:
485 12327 258
New
AstonJ
You might be thinking we should just ask who’s not using VSCode :joy: however there are some new additions in the space that might give V...
New
AstonJ
We have a thread about the keyboards we have, but what about nice keyboards we come across that we want? If you have seen any that look n...
New
dimitarvp
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...
New
mafinar
Crystal recently reached version 1. I had been following it for awhile but never got to really learn it. Most languages I picked up out o...
New
foxtrottwist
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...
New
mafinar
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...
New
New
AnfaengerAlex
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...
New

Sub Categories: