th 94 - Variable vs Get_variable: Understanding Tensorflow's Differences

Variable vs Get_variable: Understanding Tensorflow’s Differences

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th?q=Difference Between Variable And Get variable In Tensorflow - Variable vs Get_variable: Understanding Tensorflow's Differences

Have you ever wondered about the differences between Variable and get_variable in TensorFlow? These two terms may sound similar, but they function differently. If you’re a beginner in deep learning, understanding these differences can be crucial for your success.

When it comes to creating variables in TensorFlow, there are two methods: Variable and get_variable. The Variable method creates a new variable each time it’s called, while get_variable generates a variable by its name (if it already exists) or creates one if it doesn’t. So, which one should you use?

The answer to this question lies in your specific needs. If you’re building a static model, you might prefer to use Variable to create new variables. But if you’re building a dynamic model that requires multiple layers, get_variable is the way to go. The latter method allows you to reuse variables across different scopes, making it easier to manage and understand your code.

In conclusion, both Variable and get_variable serve a specific purpose in TensorFlow. While Variable is useful in certain cases, get_variable provides flexibility and reusability across different scopes. Understanding the differences between these two methods is essential to develop efficient deep learning models in TensorFlow.

So, if you want to dive deeper into the world of tensors and gain a better understanding of how Variable and get_variable differ in TensorFlow, read on! This article will provide you with detailed explanations and examples to help you master the two.

th?q=Difference%20Between%20Variable%20And%20Get variable%20In%20Tensorflow - Variable vs Get_variable: Understanding Tensorflow's Differences
“Difference Between Variable And Get_variable In Tensorflow” ~ bbaz


TensorFlow is a popular deep learning framework used for building Neural Networks. Its API provides users with two methods to create trainable variables — ‘Variable’ and ‘get_variable’.

Understanding Variables in TensorFlow

The first method, ‘Variable’, creates a new variable every time it’s called, with the same name but different instances. It has the following syntax:

 my_variable = tf.Variable(initial_value, name=name_scope)

Example of Variables in TensorFlow

Let’s look at an example of how Variable works.

import tensorflow as tfwith tf.Session() as sess:    v1 = tf.Variable(1.0)    v2 = tf.Variable(2.0)    init = tf.global_variables_initializer()    print('v1:',  # v1: 1.0    print('v2:',  # v2: 2.0    v1.assign(5.0)      print('v1:',  # v1: 5.0    print('v2:',  # v2: 2.0

Understanding get_variable In TensorFlow

The second method, ‘get_variable’ creates a new variable only if it doesn’t exist yet, and reuses it otherwise. It accepts the variable name, shape, and initializer as inputs. The syntax looks like the following:


Example of get_variable in TensorFlow

Here’s an example of how to use get_variable in TensorFlow:

import tensorflow as tf with tf.Session() as sess:    v1 = tf.get_variable(v, shape=[], initializer=tf.constant_initializer(2.0))     v2 = tf.get_variable(v, shape=[], initializer=tf.constant_initializer(3.0))    init = tf.global_variables_initializer()    print('v1:',  # v1: 2.0    print('v2:',  # v2: 2.0    v1.assign(5.0)      print('v1:',  # v1: 5.0    print('v2:',  # v2: 5.0

Advantages of Using ‘get_variable’

One of the key advantages of using ‘get_variable’ over ‘Variable’ is that it allowsthe user to reuse existing variables across different parts of the codebase.

Example of Reusing get_variable in Different Parts of the Codebase

def create_scope(scope_name):    with tf.variable_scope(scope_name) as scope:        W1 = tf.get_variable(W1, [784, 256], initializer=tf.random_normal_initializer())         b1 = tf.get_variable(b1, [256], initializer=tf.zeros_initializer())        W2 = tf.get_variable(W2, [256, 10], initializer=tf.random_normal_initializer())        b2 = tf.get_variable(b2, [10], initializer=tf.zeros_initializer())    return scope, [W1, b1, W2, b2]with tf.Session() as sess:    scope1, params1 = create_scope('my_scope')    scope2, params2 = create_scope('my_scope')    init = tf.global_variables_initializer()    print([0])) # First value of W1    print([0])) # First value of W1 (same as the above)

Performance difference between Variable and get_variable

Although there’s not a lot of noticeable performance difference between ‘Variable’ and ‘get_variable’, there are two major reasons why ‘get_variable’ should be preferred in most cases:

Fixed Memory Allocation

First, Tensorflow optimizes computation by pre-allocating a fixed chunk of memory when using get_variable, whereas Variable allocates new memory every time it’s called, which can slow down computation time when working with large models.

Resource management

The second reason ‘get_variable’ is preferred is that it allows for better resource management. Since ‘get_variable’ tracks variables in a table, it prevents variables from being created more than once, and avoids issues such as accidentally reusing the same initialization across variables. It also simplifies checkpointing and restoring variables.

Comparison Table: Variable Vs get_variable

Variable get_variable
New variable instance created every time Reuses existing variable or creates new one if required
Memory allocation issue while building large models Pre-allocate fixed memory, avoiding memory allocation issue
Causes unique name collisions Enables you to reuse existing variables
Does not manage variable scopes Better resource management and variable scope tracking


Understanding the differences between Variable and get_variable is crucial when working with TensorFlow. While the performance differences may not be significant, using get_variable is preferred because it offers better resource management and memory optimization. As a result, the majority of the TensorFlow community recommends using get_variable over Variable, except in specific use cases.

When deciding which one to use, consider things like model size and resource usage, code structure, and potential naming collisions that may occur along the way.

Thank you for reading through our article on Variable vs Get_variable: Understanding Tensorflow’s Differences. We hope that this article has provided you with a better understanding of the two concepts and their differences.

Knowing when to use Variables and Get_variables is crucial when working with Tensorflow, and we hope that you are now able to make informed decisions on which method to use when designing your neural networks.

In conclusion, Variables and Get_variables are both essential parts of Tensorflow, but they have some fundamental differences that you need to be aware of when building complex models. By choosing the right option for each scenario, you will be able to improve the performance of your machine learning applications.

People also ask about Variable vs Get_variable: Understanding Tensorflow’s Differences:

  1. What is the difference between Variable and get_variable in Tensorflow?
  2. The main difference between Variable and get_variable is that Variables are explicitly created and initialized, while get_variable automatically creates and initializes the variable if it does not exist. Additionally, get_variable allows for variable sharing across different parts of the model.

  3. When should I use Variable vs get_variable in Tensorflow?
  4. You should use Variables when you need to explicitly create and initialize a variable. This is useful when you want to define a specific shape or value for the variable. However, if you want to allow for variable sharing and automatic creation and initialization, you should use get_variable.

  5. How do Variables and get_variable affect the performance of my Tensorflow model?
  6. There is no significant difference in performance between Variables and get_variable. However, using get_variable can allow for more efficient memory usage and faster training times when variables are shared across different parts of the model.

  7. Can I convert a Variable to a get_variable or vice versa?
  8. No, you cannot convert a Variable to a get_variable or vice versa. Once a variable is created using either method, it must be used consistently throughout the model.

  9. What are some common use cases for Variables and get_variable in Tensorflow?
  10. Variables are commonly used to store weights and biases in neural networks, while get_variable is often used for variable sharing between different layers or parts of a model. Additionally, get_variable can be useful for creating reusable components or modules.