- Deep Learning Essentials
- Wei Di Anurag Bhardwaj Jianing Wei
- 296字
- 2021-06-30 19:17:46
Data representation
In this section, we will look at core data structures and representations used most commonly across different linear algebra tasks. This is not meant to be a comprehensive list at all but only serves to highlight some of the prominent representations useful for understanding deep learning concepts:
- Vectors: One of the most fundamental representations in linear algebra is a vector. A vector can be defined as an array of objects, or more specifically an array of numbers that preserves the ordering of the numbers. Each number can be accessed in a vector based on its indexed location. For example, consider a vector x containing seven days a week encoded from 1 to 7, where 1 represents Sunday and 7 represents Saturday. Using this notation, a particular day of the week, say Wednesday, can be directly accessed from the vector as x [4]:

- Matrices: These are a two-dimensional representation of numbers, or basically a vector of vectors. Each matrix, m, is composed of a certain number of rows, r, and a specified number of columns, c. Each of i rows, where 1 <= i <= r, is a vector of c numbers. Each of the j columns, where 1 <=j <= c, is also a vector of r numbers. Matrices are a particularly useful representation when we are working with images. Though real-world images are three-dimensional in nature, most of the computer vision problems are focused on the two-dimensional presentation of images. As such, a matrix representation is an intuitive representation of images:

- Identity matrices: An identity matrix is defined as a matrix which, when multiplied with a vector, does not change the vector. Typically, an identity matrix has all elements as 0 except on its main diagonal, which is all 1s:

推薦閱讀
- 基于C語言的程序設(shè)計
- Splunk 7 Essentials(Third Edition)
- AWS:Security Best Practices on AWS
- HBase Design Patterns
- Visual C# 2008開發(fā)技術(shù)詳解
- 最后一個人類
- 運動控制器與交流伺服系統(tǒng)的調(diào)試和應(yīng)用
- 數(shù)據(jù)通信與計算機網(wǎng)絡(luò)
- Linux服務(wù)與安全管理
- Linux:Powerful Server Administration
- 影視后期編輯與合成
- Docker on Amazon Web Services
- 筆記本電腦維修90個精選實例
- 在實戰(zhàn)中成長:Windows Forms開發(fā)之路
- 網(wǎng)絡(luò)管理工具實用詳解