Learner, Metrics, and Basic Callbacks | fastai
https://docs.fast.ai/learner29.11.2021 · Each Callback is registered as an attribute of Learner (with camel case). At creation, all the callbacks in defaults.callbacks ( TrainEvalCallback, Recorder and ProgressCallback) are associated to the Learner. metrics is an optional list of metrics, that can be either functions or Metric s (see below). path and model_dir are used to save and/or ...
Optimizers | fastai
https://docs.fast.ai/optimizerRAdam ( params, lr, mom = 0.9, sqr_mom = 0.99, eps = 1e-05, wd = 0.0, beta = 0.0, decouple_wd = True) A Optimizer for Adam with lr, mom, sqr_mom, eps and params. This is the effective correction reported to the adam step for 500 iterations in RAdam. We can see how it goes from 0 to 1, mimicking the effect of a warm-up.
Learner, Metrics, and Basic Callbacks | fastai
docs.fast.ai › learnerNov 29, 2021 · For instance, fastai's CrossEntropyFlat takes the argmax or predictions in its decodes. Depending on the loss_func attribute of Learner, an activation function will be picked automatically so that the predictions make sense. For instance if the loss is a case of cross-entropy, a softmax will be applied, or if the loss is binary cross entropy ...
Optimizers | fastai
docs.fast.ai › optimizerQHAdam is based on QH-Momentum, which introduces the immediate discount factor nu, encapsulating plain SGD (nu = 0) and momentum (nu = 1). QH-Momentum is defined below, where g_t+1 is the update of the moment. An interpretation of QHM is as a nu-weighted average of the momentum update step and the plain SGD update step.
Lesson 2 - Stochastic Gradient Descent | walkwithfastai
walkwithfastai.com › SGDBelow you will find the exact imports for everything we use today. import torch from torch import nn import numpy as np import matplotlib.pyplot as plt from fastai.torch_core import tensor. Stochastic Gradient Descent (SGD): Optimization technique ( optimizer) Commonly used in neural networks. Example with linear regression.