• Building neural networks from scratch with Python


    By Rashida nasrin suckyCompile VKSource: medium Neural networks have been developed to simulate the human brain. Although we haven’t done that yet, neural network is very effective in machine learning. It was very popular in the 1980s and 1990s and has become more and more popular recently. The computer is fast enough to run a […]

  • Summary of loss function in Python


    Interactive segmentation practical knowledge note 2 How to select the loss function is one of the problems that must be considered when training network in deep learning. In recent years, focal loss is very popular in segmentation, but many projects still use basic dice, crossentropy and other basic loss functions, and the effect difference is […]

  • Weekly canvas animation — circular motion


    Next to “weekly canvas animation” — wave motion Circular motion can be divided into two basic formsCircular motionandElliptical motion。Before explaining circular motion, the essential mathematical formula is about to come. So, ladies and gentlemen, please protect your knees. It doesn’t matter if you don’t understand, just understand the principle. Of course, can understand is the […]

  • Graphics processing: filling canvas text with linear gradients


    Author: barrior In canvas, it is easy to fill the text with horizontal or vertical linear gradients, while the gradients with angles are much more complex. As shown below, suppose the width of the text rectangle isW, Gao WeiHThe coordinates of the upper left corner areX, Y。 Guess and answer Give two answers: The correct […]

  • PTA C language 7-6 cm converted to FT in


    7-6 cm to FT in If the values of foot and inch are known, the corresponding meter is (foot + inch / 12) × 0.3048. Now, if the user enters centimeters, what are the feet and inches corresponding to the English length? Don’t forget that one foot is 12 inches. analysis The first time I […]

  • Bid farewell to hard coding and let your front-end table calculate automatically


    GitHub | Demo | Blog | Original link preface When my team developed the tax system module, I found that they needed to spend 80% of their time to solve the calculation problems, especially in the calculation in the grid Write the foreground JS code (because the user’s input in the table will affect other […]

  • Detailed explanation of RSA algorithm


    What is RSA In the previous article, we talked about AES algorithm. AES algorithm is a symmetric encryption algorithm. In this paper, we will introduce a very common asymmetric encryption algorithm RSA. Asymmetric encryption algorithm, also known as public key cryptography algorithm, encrypts and decrypts plaintext ciphertext by generating public and private keys. RSA’s name […]

  • Leetcode 1014. Best sightseeing combination | Python


    1014. Best sightseeing combination Title Source: leetcode https://leetcode-cn.com/problems/best-sightseeing-pair subject Given a positive integer array a, a [i] represents the score of the ith scenic spot, and the distance between two scenic spots I and j is J – I. The score of a tourism combination composed of a pair of scenic spots (I < J) […]

  • The types and differences of t test in Statistics


    As we said earlier, t-test is a test method used to compare whether there is a significant difference between two means. This article introduces the types of t-test and the specific Python implementation code. T-test is to compare the difference between two means. The difference of different kinds of t-test is actually the difference of […]

  • Excel like component based on Vue + canvas


    vue-grid-canvas Vue component, a form component based on Vue, is mainly used to solve the performance problem of large amount of data table rendering. It uses canvas to draw tables, and supports functions like batch selection, copy, paste, delete, real-time editing of Excel. At present, it is still improving. I hope your star will be […]

  • A simple formula calculation tool class


    import java.math.BigDecimal; import java.util.*; /** *Simple formula calculation tool, only support +, -, *, /, () * @author ningyongli * @date 2020-07-13 */ public class CalculateUtils { private static final Map<String, Integer> PRIORITY_MAP = new HashMap<>(); private static final List<String> OPERATOR_LIST = new ArrayList<>(); static { PRIORITY_MAP.put(“(“, 0); PRIORITY_MAP.put(“+”, 5); PRIORITY_MAP.put(“-“, 5); PRIORITY_MAP.put(“*”, 10); PRIORITY_MAP.put(“/”, […]

  • Linear regression: principle and implementation of gradient descent method


    catalog 1、 Linear regression 2、 Mathematical principle of gradient descent method 3、 Optimization of gradient descent method 4、 Python implementation 1、 Linear regression    for a detailed introduction of linear regression, please refer to my last blog postLinear regression: the realization of least square method. In “linear regression: the realization of the least square method”, […]