Blog

Learn About Our Meetup

5000+ Members

MEETUPS

LEARN, CONNECT, SHARE

Join our meetup, learn, connect, share, and get to know your Toronto AI community. 

JOB POSTINGS

INDEED POSTINGS

Browse through the latest deep learning, ai, machine learning postings from Indeed for the GTA.

CONTACT

CONNECT WITH US

Are you looking to sponsor space, be a speaker, or volunteer, feel free to give us a shout.

[P] Convolutional networks with NumPy, or let’s learn how a CNN really works!

Although I have spent quite a lot of time recently with CNNs for image classification and semantic segmentation, I have realized that to obtain a deep understanding of them, I have to make one on my own from scratch. So, I put down PyTorch, my go-to framework, and created an implementation using NumPy only 🙂

The result can be found here: https://github.com/cosmic-cortex/neural-networks-from-scratch

Basically, it is a mini deep learning framework, so one can easily experiment with different architectures. Currently, the following components are supported.

Layers:

  • Linear
  • Conv2D
  • BatchNorm2D
  • MaxPool2D
  • Flatten (technically, this is not a layer, since it just flattens a 2D input, but it was very convenient to implement this as one)

Loss functions:

  • CrossEntropyLoss
  • MeanSquareLoss

Activation functions:

  • ReLU
  • Leaky ReLU
  • Sigmoid

There are two examples as well, a simple multilayer perceptron and a basic CNN on MNIST classification, but custom datasets are supported as well, if you would like to experiment on your own data.

I have to say, I have really enjoyed this ride! It was extremely instructional, moreover I have discovered several mindblowing details, for instance that the gradient for convolution is a transpose convolution operator 🙂 Truly recommended for everyone in DL/ML to try doing the same. During this venture, the fantastic CS231n course was very helpful, so this is also recommended.

submitted by /u/cosmic-cortex
[link] [comments]

Next Meetup

 

Days
:
Hours
:
Minutes
:
Seconds

 

Plug yourself into AI and don't miss a beat

 


Toronto AI is a social and collaborative hub to unite AI innovators of Toronto and surrounding areas. We explore AI technologies in digital art and music, healthcare, marketing, fintech, vr, robotics and more. Toronto AI was founded by Dave MacDonald and Patrick O'Mara.