• Based on the source, grasp the law


    “Multiplication distribution law” is an important operation law in primary school, which is used in the solution of many problems. “Multiplication distribution law” is the knowledge basis for learning algebraic simplification and formula induction in the future, which has important value and position in mathematics learning. Its biggest difference from multiplication exchange law and combination […]

  • Sass operation


    In this section, we learn about the operations in sass, which are supported in general programming syntax. Sass can also do various mathematical operations, including the most basic addition, subtraction, multiplication and division, variable operation, color operation, character operation, etc. In this section, we mainly talk about the most basic mathematical operations in sass. Addition […]

  • Basic functions of dealing with tensors in five pytorch


    Basic functions of dealing with tensors in five pytorch Every beginner of deep learning should know these five basic functions of pytoch. Being able to construct neural networks in an accurate and effective way is one of the most sought after skills of recruiters in deep learning engineers. Pytorch is a python library mainly used […]

  • [mindspire: machine learning with little MI] those knowledge points of linear algebra that we are about to forget


    I haven’t seen it in a week. The power doesn’t decrease! Little Mi meets you again with knowledge! (knock on the blackboard ~) Last week, Xiao Mi took you to learn the concept of machine learning and its two common categories, supervised learning and unsupervised learning. This time, Xiao Mi decided to review the knowledge […]

  • Toom cook large integer multiplication


    Algorithm Introduction stayKaratsuba divide and conquer multiplicationIn this article, I introduce Karatsuba divide and conquer multiplication. By dividing the two numbers into two segments, its time complexity can be achieved\(T(n) = O(n^{\log_23})=O(n^{1.585})\)。 This article will extend Karatsuba algorithm, further discuss divide and conquer multiplication, and introduce toom cook algorithm with lower time complexity. In fact, […]

  • CSAPP English Learning Series: Chapter 2: data representation


    Series articles: CSAPP English Learning Series: Preface CSAPP English Learning Series: Chapter 1: a tour of computer systems CSAPP English Learning Series: Chapter 2: data representation CSAPP English Learning Series: Chapter 8: exceptional control flow CSAPP English Learning Series: Chapter 11: network programming CSAPP English Learning Series: Chapter 12: concurrent programming Generally speaking, binary operations […]

  • [machine learning notes]: boasting linear regression (I)


    Hello, I’m Dongge. As one of the classical regression models in supervised learning, linear regression is a very good start for beginners. Considering the concept of comprehensiveness from a macro perspective, I think we may have been in contact in junior middle school. Y = ax, X is the independent variable, y is the dependent […]

  • Weighted least squares in Statistical Science


    Today, we will talk about the weighted least squares (WLS), which is based on the ordinary least squares regression (OLS), and is mainly used to solve the heteroscedasticity problem. The general form of OLS is as follows: As we mentioned earlier, OLS has several basic assumptions. One of them is that UI is a random […]

  • Linear regression: the realization of least square method


    catalog 1、 Linear regression 2、 Least square method 3、 Least square method (vector representation) 4、 Python implementation 1、 Linear regression    given the sample x = (x0, x1, X2,…, xn) described by N attributes,linear modelTry to learn a suitable linear combination of sample attributes to perform the prediction taskf(x) = w1x1 + w2x2 + … […]

  • Integer ring


    ring Integer ringZ_mIt consists of the following two parts: 1. AssemblyZ_m = ( 0,1,2,…,m )2. Two kinds of operations “+” and “X” make thea, b\in Z_myes: a + b\equiv c\ mod\ m, (c\in Z_m)\\ a\times b\equiv d\ mod\ m, (d\in Z_m) Key features of rings If the result of the addition or multiplication of any […]

  • CSP-S-2020


    CSP-S-2020 T1 Julian day Give the highest respect (kowtow) to the T1 author. T2 Zoo Give some numbers, guarantee\(x∈[1,2^k-1]\)And different from each other, some conditions are given if there are numbers\(x\)The first\(ai\)Bit is\(1\)Then you have to choose the item\(bi\),\(bi\)They are different. How many numbers are there\(y\)Satisfaction does not exist\(x=y\)And add\(y\)Post selected\(b\)unchanged. It is easy to […]

  • On binary (2) – four operations


    (Note:SegmentfaultThe mathematical formula in the article isBUGWhen previewing, it is good. When the article is sent out, it will show that there is a problem. If you have any problem when you read it, you can move on http://www.dubingxuan.com/article/8/ ) Preface In the last article about binary system (1), we spent a lot of space, […]