
mwomick
The Ray Tracer Challenge: p. 28
The Ray Tracer Challenge by @jamis: p. 28
It appears to me that on page 28, there is an error. The first column of the features/matrices.feature A*B matrix is:
20
44
40
16
whereas my program computed
8
8
-8
-8
Is this an error or have I gotten something wrong?
Marked As Solved

jamis
Author of Mazes for Programmers and 1 other title
It looks like you might have a typo in your second matrix (“B”). In the second row, the first number is a positive “3”, rather than negative. That should get you the expected answer.
- Jamis
1
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