QCustomplot uses sharing-drawing charts-loading cvs files
I. Overview
I have made a financial product before, the name is Cailianshe. If you are interested, you can take a look at Cailianshe-Product Display. Since I need to draw complex k-line diagrams and some auxiliary charts, I personally researched several drawing libraries. Including: QWt, QCustomPlot, QtChart and directUI. Finally, all partie ...
Posted by bqallover on Fri, 06 Jan 2023 15:07:50 +0300
SQL statement exercises
1. Select all employees in department 30;
Note: All employees are to be checked
scoped to sector 30
code show as below:
mysql> select * from emp where deptno = 30;
2. List the names, numbers and department numbers of all clerks (CLERK);
Note: What you want to check is name, serial number and department serial number
clerk
code sh ...
Posted by TylerL on Thu, 05 Jan 2023 18:21:51 +0300
this.$route.params is empty after refreshing the page
this.$route.params is empty after refreshing the pageWhen studying vue-router in depth, I followed the tutorial of the official document and found that after refreshing the page, the printed this.$route.params is emptyVue2Problem recurrenceRouting configuration:import Vue from "vue";
import VueRouter from "vue-router";
Vue.use(VueRouter);
con ...
Posted by hawk72500 on Thu, 05 Jan 2023 11:58:26 +0300
Python Basics - Numpy Numerical Calculation
NumPy provides a multidimensional array object called ndarray whose elements have a fixed size. That is, NumPy array elements are homogeneous and can only store objects of the same data type. It can use vectorized operation to process the entire array, which has high operation efficiency.
array creation
Create an ndarray array through the arr ...
Posted by Elle0000 on Wed, 04 Jan 2023 20:32:18 +0300
dubbo source code practice - example of serialize layer
Table of contents
1 serialize layer overview
2 Simple example of serialization
2.1 Screenshot of the project
2.2 The source code of the three classes
2.2.1 ABC is an entity class
2.2.2 TestSeriarsWrite serializes ABC objects into files
2.2.3 TestSeriarsRead reads ABC objects from the file
2.2.4 Running Results
3 Show an example of dy ...
Posted by davidb on Tue, 03 Jan 2023 19:47:43 +0300
Database Study Notes
Database Study Notes (2)1. Database Security1.1 TCSEC/TDI security level classificationB1 level: "secure" or "trusted" products, truly secure products1.2 Database management system security control modelAccess control process:The database management system authenticates the database users who make SQL access requests to prev ...
Posted by speedyslow on Mon, 02 Jan 2023 10:48:29 +0300
C++ classes and dynamic memory allocation
1. Dynamic memory and classes
Static data members are declared in the class declaration and initialized in the file containing the class methods. The scope operator is used during initialization to indicate the class to which the static member belongs. If the static member is an integral or enumeration type const, it can be initialized in the ...
Posted by rocket on Sun, 01 Jan 2023 23:52:07 +0300
Metrics type in Prometheus
From the perspective of storage, all monitoring indicators are the same, but there are some subtle differences in these metric s in different scenarios. For example, the indicator node_load1 in the sample returned by Node Exporter reflects the current system load status, and the sample data returned by this indicator is constantly changing as ...
Posted by mk_silence on Sun, 01 Jan 2023 14:17:59 +0300
The most comprehensive microservice permission control scheme in history
1. Microservice permission design
Let me first talk about why I wrote this article, because the actual project needs, we need to control the permissions of each component of our current project page, and then check the commonly used permission frameworks on the Internet, one is shrio, the other is spring security, After reading the comparison, ...
Posted by Travis Estill on Sun, 01 Jan 2023 10:22:23 +0300
Algorithm training camp DAY2_Squaring of ordered arrays, subarrays with the smallest length, spiral matrix II
LeetCode | 977. Squaring an Ordered Array
topic:
Given an array of integers nums sorted in non-decreasing order, return a new array consisting of the square of each number, also sorted in non-decreasing order.
977. Squaring an Ordered Arrayhttps://leetcode.cn/problems/squares-of-a-sorted-array/
think:
When I first thought about the solutio ...
Posted by bloo on Sat, 31 Dec 2022 14:42:36 +0300