Feng's Notes Isn't coding fun?

Backward propagation of Neural Network explained

Backpropagation is the foundation of the deep neural network. Usually, we consider it to be kind of ‘dark magic’ we are not able to understand. However, it should not be the black box which we stay away. In this article, I will try to explain backpropagation as well as the whole neural network step by step in the original mathematical way.

Stochastic gradient descent

Stochastic Gradient decent is one of the fundamental algorithm in deep learning. It is used when we perform optimization of the cost function.Suppose the function is $ f(x) $

sgd

[Pandas]How to plot counts of each value

[Pandas]How to calculate datetime difference in years

Suppose you got a person’s regist time in one column and his birth date in another column, now you need to calculate his age when he did the registration. There are two ways to reach this result.

[Pandas]How to list all columns

[Pandas] How to import from Sql Server

We need to rely on pyodbc, the sample code is as belows.

Basics of words embedding

Why embedding

Natural language processing systems traditionally treat words as discrete atomic symbols, and this may lead to some obstacles in word preprocessing:

What is tf.data and how to use

Tf.data is a high level API provided by tensorflow, it performs as a pipeline for complex input and output. The core data structure of tf.data is Dataset which represents a potentially large set of elements.

[Pandas]Handle missing data

Missing data is a common problem in real data preprocessing, luckily pandas has done a lot to help us handle it. This article will show the codes on how to do it.

[Pandas]How to select data

This article shows the most common methods regarding data selection