C3_W2_RecSysNN_Assignmen square-distance issue

Course Q&A Machine Learning Specialization Unsupervised Learning, Recommenders, Reinforcement
1

I understand that calculating the square distance between 2 arrays, you can do that in one line. How can I show my line (that doesn’t work)?

2

Hi @Alain

Have you had a look at the hint? If you click on that, you will see text expansion giving suggestions on the functions to use for this calculation.

3

Hi @Kic

I have read it as well as related posts but I’m still stuck. My line doesn’t work.

4

Hi @Alain

So let’s break down the steps to get it working:

  • subtract numpy array ‘a’ from ‘b’ elementwise. You can do that by using np.substract() function or simply a - b
  • use np.square() to get the square of each resulting elements
  • use np.sum() to add all the squared elements to give you a scalar value for the distance.
2 Likes
5

Thanks @Kic for your helpful guidance. I was going on some crazy tangent by looking up other crazy methods in tensorflow.

Thanks again and take care,
Alain

6

thank you for this guidance I was stuck as well, its very simple, 3 points explained, 3 lines of code

7

Hello did you made any definition of a or b?, I get a message that ““module ‘numpy’ has no attribute ‘substract’””

I’m not sure if only a,b should be inside the substract or how it should go, thanks in advance.

8

Hello @Tadeo_Rodriguez,

Here is an explaination of squared distance. If you want to do element-wise subtraction, you may use this numpy function.

Cheers,
Raymond

9

hi, I’m using that function, but for some reason, it is not working properly. It shows me the message of “module ‘numpy’ has no attribute ‘substract’”, hence my question if I should declare in any space “a” and “b”, on the numpy guidance I don’t see anything different.

{code removed by mentor}

10

Hello @Tadeo_Rodriguez,

Check the spelling of subtract, not substract. :wink:

Raymond

11

looooool hahah, thanks raymond, have a good weekend.