• Getting started with simple MD


    An entry note of mark down Experience I always thought that the writing method of MD file would be very complex, and then I found it was so simple after contacting it that I could start in 3 minutes. With some simple symbols, you can write a clean page. Use her, will gradually fall in […]

  • learning OpenCV3 – data type


    three classes of initials basic data types Usually inherited from C + + int, float, etc vectors,matrices,simple geometric concepts like points, rectangles,sizes helper objects Represents some more abstract concepts garbage-collecting pointer class range objects used for slicing abstractions such as termination criteria large array types contain arrays or other assemblies of primitives or, more often, […]

  • Linux crontab command parameters and time format description


    Crontab is used to let users execute programs at a fixed time or interval Parameter description option function -e Edit crontab scheduled tasks -l Query crontab task -r Delete all crontab tasks of the current user Time format project Meaning Range First “*” The first few minutes of an hour 0-59 Second “*” Hours of […]

  • Group by LINQ expression based on multiple fields in C × set


        void Main() { var empList =new List { new Employee {ID = 1, FName = “John”, Age = 23, Sex = ‘M’}, new Employee {ID = 2, FName = “Mary”, Age = 25, Sex = ‘F’}, new Employee {ID = 3, FName = “Amber”, Age = 23, Sex = ‘M’}, new Employee {ID […]

  • Single table serialization and single table deserialization


    from rest_framework import serializers from django.db import models Student list class Student(models.Model):   Name = models. Charfield (max? Length = 32) ා student name   IMG = models. Charfield (max? Length = 255)   class Meta:     DB table =’student ‘ා table name Student list的序列化 class StudentSerializer(serializers.ModelSerializer):   class Meta:     Model = student table name     Fields = ‘× all × […]

  • Ubuntu install gitlab runner


    Step one: Add gitlab’s official Repository: curl-L https://packages.gitlab.com/install/repositories/runner/gitlab-runner/script.deb.sh | sudo bash The second step: Install the latest version of gitlab runner: apt getinstall gitlab-runner It’s already installed You can start to register the runner The command is: gitlab runner register After input, the first step will appear: Please enter the gitlab CI coordinator URL (e.g. […]

  • 1. Pyplot basic syntax


    Catalog 1. Pyplot basic syntax 2. Scatter chart and line chart 3. 3D map and contour map 1. Pyplot basic syntax (1) Create canvasFigure () creates a blank canvas. You can specify the size of the canvas, figsize, and set the resolution DPI plt.figure() PLT. Figure (figsize = (8,6), DPI = 80) ා (8,6) represents […]

  • Cross domain problem handling between yii2 and Vue


    Add the following to the controller header(“Access-Control-Allow-Origin: *”); //If you need to set up a cross domain request that allows all domain names to initiate, you can use the wildcard * to write your own domain name if you restrict your domain name. //The response type * represents a wildcard, which can indicate fixed types […]

  • Getting started with regular expressions written to the front end


    1. overview stayJavaScriptUse in//To create a regular expression object, you can also usenew RegExp() Common methods related to regularization arematch、testandreplace。amongmatch,replaceThey’re all methods on strings,testIs a method on a regular object. See the specific figure below: 2. Match single character /reg/You can match specific strings directlyreg。 /[arzy]/Brackets in[]MatcharzyAny single character in /[f-h]/Middle bar-In the matching alphabet […]

  • VIM master, never use a mouse


    VIM steps out of the mouse In normal times, VIM is indispensable, but it can’t be avoided. In fact, it’s completely possible to omit the mouse. It’s not as difficult as you think. Look at my short lines and take you to omit the mouse. By the way, VIM has three modes. The basic mode […]

  • Review: basic knowledge of C language 1


    Placeholder: %D,% I, for integer,% f-floating point,% s, string,% C, char.% P pointer,% FL long long,% e scientific count,% G decimal or scientific count. Format placeholders in C: %A,% a reads a floating-point value (p-count (hex count), C99 only) %C read in a character %D read in decimal integer %E convert numerical value to exponential […]

  • Linux related collections


    This article is an overview. Linux xshell6 connection Hadoop Start and Close   Linux xshell 6 connection related issues   First of all, virtual machines have to be networked (Baidu can be a specific tutorial) Then, query the native IP (xshell 6 connection key) ==> IP addr   Finally, connect xshell6   Then connect.   Hadoop […]