Een lineair model trainen in batches

In deze oefening trainen we een lineair regressiemodel in batches, voortbouwend op de vorige oefening. We lopen in stappen door de gegevensset en updaten na elke stap de modelvariabelen intercept en slope. Met deze aanpak kun je trainen met gegevenssets die anders te groot zijn om in het geheugen te passen.

Let op: de verliesfunctie loss_function(intercept, slope, targets, features) is al voor je gedefinieerd. Daarnaast is keras geïmporteerd en is numpy beschikbaar als np. Voer de trainbare variabelen in var_list in, in dezelfde volgorde als waarin ze als argumenten van de verliesfunctie voorkomen.

Deze oefening maakt deel uit van de cursus

Introductie tot TensorFlow in Python

Cursus bekijken

Oefeninstructies

Gebruik de .Adam()-optimizer.
Laad de data uit 'kc_house_data.csv' in batches met een chunksize van 100.
Haal de kolom price uit batch, zet deze om naar een numpy-array van het type 32-bits float en ken deze toe aan price_batch.
Maak de verliesfunctie compleet, vul de lijst met trainbare variabelen in en voer de minimisatie uit.

Praktische interactieve oefening

Probeer deze oefening eens door deze voorbeeldcode in te vullen.

# Initialize Adam optimizer
opt = keras.optimizers.____

# Load data in batches
for batch in pd.read_csv('____', ____=____):
	size_batch = np.array(batch['sqft_lot'], np.float32)

	# Extract the price values for the current batch
	price_batch = np.array(batch['____'], np.____)

	# Complete the loss, fill in the variable list, and minimize
	opt.minimize(lambda: loss_function(____, slope, price_batch, size_batch), var_list=[intercept, ____])

# Print trained parameters
print(intercept.numpy(), slope.numpy())

Code bewerken en uitvoeren

Deze oefening maakt deel uit van de cursus

Introductie tot TensorFlow in Python

SkillTag.level.intermediateSkillTag.label

4.8+

Begin de cursus gratis

Before you can build advanced models in TensorFlow 2, you will first need to understand the basics. In this chapter, you’ll learn how to define constants and variables, perform tensor addition and multiplication, and compute derivatives. Knowledge of linear algebra will be helpful, but not necessary.

Exercise 1: Constants and variables Exercise 2: Defining data as constants Exercise 3: Defining variables Exercise 4: Basic operations Exercise 5: Performing element-wise multiplication Exercise 6: Making predictions with matrix multiplication Exercise 7: Summing over tensor dimensions Exercise 8: Advanced operations Exercise 9: Reshaping tensors Exercise 10: Optimizing with gradients Exercise 11: Working with image data

In this chapter, you will learn how to build, solve, and make predictions with models in TensorFlow 2. You will focus on a simple class of models – the linear regression model – and will try to predict housing prices. By the end of the chapter, you will know how to load and manipulate data, construct loss functions, perform minimization, make predictions, and reduce resource use with batch training.

Exercise 1: Invoergegevens Exercise 2: Gegevens laden met pandas Exercise 3: Het gegevenstype instellen Exercise 4: Verliesfuncties Exercise 5: Verliesfuncties in TensorFlow Exercise 6: De verliesfunctie aanpassen Exercise 7: Lineaire regressie Exercise 8: Een lineaire regressie opzetten Exercise 9: Train een lineair model Exercise 10: Meervoudige lineaire regressie Exercise 11: Batchtraining Exercise 12: Voorbereiden op batchtraining Exercise 13: Een lineair model trainen in batches

Huidige oefening

The previous chapters taught you how to build models in TensorFlow 2. In this chapter, you will apply those same tools to build, train, and make predictions with neural networks. You will learn how to define dense layers, apply activation functions, select an optimizer, and apply regularization to reduce overfitting. You will take advantage of TensorFlow's flexibility by using both low-level linear algebra and high-level Keras API operations to define and train models.

Exercise 1: Dense layers Exercise 2: The linear algebra of dense layers Exercise 3: The low-level approach with multiple examples Exercise 4: Using the dense layer operation Exercise 5: Activation functions Exercise 6: Binary classification problems Exercise 7: Multiclass classification problems Exercise 8: Optimizers Exercise 9: The dangers of local minima Exercise 10: Avoiding local minima Exercise 11: Training a network in TensorFlow Exercise 12: Initialization in TensorFlow Exercise 13: Defining the model and loss function Exercise 14: Training neural networks with TensorFlow

In the final chapter, you'll use high-level APIs in TensorFlow 2 to train a sign language letter classifier. You will use both the sequential and functional Keras APIs to train, validate, make predictions with, and evaluate models. You will also learn how to use the Estimators API to streamline the model definition and training process, and to avoid errors.

Exercise 1: Defining neural networks with Keras Exercise 2: The sequential model in Keras Exercise 3: Compiling a sequential model Exercise 4: Defining a multiple input model Exercise 5: Training and validation with Keras Exercise 6: Training with Keras Exercise 7: Metrics and validation with Keras Exercise 8: Overfitting detection Exercise 9: Evaluating models Exercise 10: Training models with the Estimators API Exercise 11: Preparing to train with Estimators Exercise 12: Defining Estimators Exercise 13: Congratulations!