Background: Participating in an interactive chart project, the customer had a need for polar coordinate comparison to display different types of indicator data in different directions and distances. Specifically, the attribute fields are: Source, distance, orientation, ID, rotation angle, size Let’s look at the renderings first: Technical points: Legend description: The distance is the radial […]
Tag: distance
LC-1334. The city with the fewest neighbors within the threshold distance (Floyd algorithm, memorized search ==> dynamic programming (0x3f))
1334. The city with the fewest neighbors within the threshold distance medium There are n cities, numbered from 0 to n-1. Give you an edge array edges, where edges[i] = [fromi, toi, weighti] represents fromi and toi code> A bidirectional weighted edge between two cities, the distance threshold is an integer distanceThreshold. Returns the city […]
MySQL face vector, Euclidean distance similarity query
Foreword For example, the title uses the extracted face feature vector to write a Euclidean SQL statement to query the top_K data records with the highest similarity in the database. Although the approach is alternative, there is a ready-made facial retrieval API on the market at the business layer, and there is now a vector […]
Intelligent ultrasonic following distance display car based on 51 microcontroller
1 Introduction In the past two years, the requirements and difficulty of graduation projects and graduation defenses have continued to increase. Traditional graduation projects lack innovation and highlights, and often fail to meet the requirements for graduation defenses. In the past two years, junior students and junior students have constantly told Senior Xiaohong to do […]
Linux driver HC_SR04 distance sensor usage reference and simple notes
Foreword HC_SR04 This distance sensor interface is relatively simple. Simply implement a driver as a learning example. Driver file #include <linux/init.h> #include <linux/module.h> #include <linux/unistd.h> #include <linux/fs.h> #include <linux/cdev.h> #include <linux/gpio.h> #include <mach/platform.h> #include <linux/uaccess.h> #include <linux/device.h> #include <linux/sched.h> #include <linux/irq.h> #include <linux/interrupt.h> #include <linux/timer.h> #include <linux/wait.h> #include <linux/platform_device.h> #include <linux/slab.h> #include <linux/delay.h> #include <linux/sched.h> […]
[Monocular Ranging] How to measure distance when the slope of the ground is known
Article directory I. Introduction 2. Ranging code 2.1. The ground has a slope 2.2. python code 2.2.1. Rotation matrix rotation angle 2.2.2. Angle to rotation matrix 2.2.3. Three-dimensional rotation principle (Rotation principle) 2.2.4. Complete code 2.3, c++ code 1. Preface The previous blog [Monocular Ranging] How to measure distance when the camera angle is known […]
[Mathematical formula derivation] Meng Xiong [csp-noip ten consecutive test set 6] T2 distance
Thanks to Jayun for technical support Original question formula: ∑ i = 1 n ∑ j = i + 1 n ( ( x i ? x j ) 2 + ( y i ? y j ) 2 ) \sum_{i=1}^{n}\sum_{j=i + 1}^{n}{((x_i-x_j)^2 + (y_i-y_j)^2)} i=1∑n?j=i + 1∑n?((xixj?)2 + (yiyj?)2) Just consider first x x […]
NOIP2023 simulates 7 joint test 28 distance
The main idea of the title give one n n An unrooted tree with n nodes, each edge has an edge weight. w i w_i wi?. make d i s ( x , y ) dis(x,y) dis(x,y) is a point x x x to point y y y distance. You need to maintain an initially […]
[Algorithm Challenge] The shortest distance between characters (including parsing and source code)
821.The shortest distance between characters https://leetcode-cn.com/problems/shortest-distance-to-a-character/ 821.The shortest distance between characters Question description Solution 1: Center expansion method Ideas Complexity analysis Code (JS/C++) Solution 2: Exchange space for time Ideas Complexity analysis Code (JS/C++) Solution 3: Greedy Ideas Complexity analysis Code (JS/C++/Python) Solution 4: Window Ideas Complexity analysis Code (JS/C++/Python) Title description Given a string […]
A brief discussion on the edit distance algorithm
Interview questions In a long string, search for a short string. The short string may have some noise, that is, some fields do not match, and the short string is about one percent of the length of the long string. How to quickly find this short string? string. At that time, the interviewer reminded me […]