• 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”, […]

  • Chapter three: pythagorean array and unit circle


    We describeda^2 + b^2 = c^2All integer solutions ofa,b,c, ifc^2Divide by this equation (\frac{a}{c})^2 + (\frac{b}{c})^2 = 1 So rational numbers are right(\frac{a}{c},\frac{b}{c})It’s an equationx^2 + y^2 = 1The solution ofequationx^2 + y^2 = 1Represents a circle C with a center at (0, 0) radius of 1. How to find the points on circle C […]

  • Npoi usage


    The pit of createrow getrow //Create row can only be used once for the same row sheet.CreateRow(startrow).CreateCell(0).SetCellValue(1); sheet.GetRow(startrow).CreateCell(1).SetCellValue(1); sheet.GetRow(startrow).CreateCell(2).SetCellValue(1); Input values and formulas //Value sheet.GetRow(startrow).CreateCell(2).SetCellValue(1); //Formula string kaohe = “O” + realrow + “-” + “I” + realrow + “+” + “R” + realrow; String shenchanjieyou = “if (isblock (R” + realrow + “),” production […]

  • Common i2i algorithm based on CF


    I2i (item to item) algorithm based on collaborative filtering is the most widely used recall algorithm in recommendation system. The base model, which is usually used as the start-up stage, is the benchmark of the subsequent algorithm iteration. It has the characteristics of convenient development and fast training speed, and the general effect is not […]

  • Add silky water ripples to the view


    Let’s take a look at the final renderings First of all, we can split such a smooth water ripple A regular curve. The curve moves to the right uniformly. The position below the curve is colored. So let’s start with a curve. For the curve that needs to produce such a regular fluctuation, we should […]