QA Official

Machine Learning -CrossValidation Cross-Validate Python Implementation

https://qaofficial.com/post/2019/04/14/70198-machine-learning-crossvalidation-cross-validate-python-implementation.html 2019-04-14
Copyright Statement: This article is original. Please indicate the source for reprinting. 1. Principle 1.1 concept Cross-validation is mainly used in model training or modeling applications, such as classification prediction, PCR, PLS regression modeling, etc.In a given sample space, most samples are taken as training sets to train the model, and the remaining small samples are predicted using the newly established model, and the prediction error or prediction accuracy of

Priorities and Combinations of Operators and Various Operators in Java and Arrangement of Precautions

https://qaofficial.com/post/2019/04/14/70078-priorities-and-combinations-of-operators-and-various-operators-in-java-and-arrangement-of-precautions.html 2019-04-14
(1) Arithmetic Operator Java运算符 算术运算符 代数表达式 Java表达式 加 + a+1 a+1 减 - a-b a-b 乘 * ab a*b 除 / a/b a/b 求模/余 % a mod b a%b Note: 1 > there is no power arithmetic operator in Java 2 > there are no operators in

Start and shut down Oracle rac database cluster

https://qaofficial.com/post/2019/04/14/70088-start-and-shut-down-oracle-rac-database-cluster.html 2019-04-14
Just like learning the operating system, after installing rac clusters, the first thing to do is to learn how to start and shut down rac. Generally, there are three ways to start and shut down RAC: sqlplus,srvctl, dbconsole or oracle grid control. This section briefly introduces the use of srvctl to start and shut down RAC database clusters! Use crs_stat command to query whether asm instance, listener, Global Service Daemon,

System Skills and Fault Handling

https://qaofficial.com/post/2019/04/14/70092-system-skills-and-fault-handling.html 2019-04-14
Modify the right-click menu of the file (such as adding an opening method)运行注册表编辑器,打开“我的电脑/HKEY_CLASSES_ROOT/*/shellex/ Contex

Which folders in Windows system can be deleted

https://qaofficial.com/post/2019/04/14/70091-which-folders-in-windows-system-can-be-deleted.html 2019-04-14
windows文件夹中的哪些文件可以删除 经过以下的设置后,你的系统会更加清爽、简洁、高效! 1.打开“我的电脑”-“工具”-“文件夹选项”-“

cross-validation in Machine Learning

https://qaofficial.com/post/2019/04/14/70204-cross-validation-in-machine-learning.html 2019-04-14
Cross validation. Cross validation is used to prevent over-fitting caused by too complex a model. It is sometimes called cyclic estimation.It is a practical method to cut data samples into smaller subsets statistically.Therefore, one subset can be analyzed first, while the other subsets are used for subsequent confirmation and verification of this analysis.The initial subset is called the training set.The other subsets are called validation set or test sets.Cross-validation is to evaluate the generalization ability of statistical analysis and machine learning algorithms to data sets independent of training data.

operators of C programming language expression

https://qaofficial.com/post/2019/04/14/70045-operators-of-c-programming-language-expression.html 2019-04-14
1. Classification C language has 34 operators and 10 types of operations: arithmetic operators (+,-,*,/,%), relational operators (>, > =, = =,!=, <, < =), positional operator (> >, < <, = =,!=, <, < =), logical operators (!, | |,&&), conditional operators, (?:) Pointer Operator (&,*), assignment (=), comma operator (,), Byte Operator (sizeof), forced type conversion Operator ((Type Name)), Others (Subscript [], Component, Function);According to the number of objects involved in the operation, operators of C programming language can be divided into single-purpose operators (such as!

optimization of baidu kityminder

https://qaofficial.com/post/2019/04/14/70097-optimization-of-baidu-kityminder.html 2019-04-14
2017-03-14 Target: Optimize brain map to make its operation smoother question: When there are too many brain map nodes, initialization rendering is slow. When adding, deleting, modifying and moving nodes, the page is blocked and other operations cannot be performed. Reason: too many nodes, initialization, import and rendering operations take a long time. too many nodes, rendering again, layout operation takes a long time dom too many, even some small changes will cause html redrawing rearrangement, resulting in page stuck solution: Minimize dom on the page When the brain map is initialized, it is only rendered to level 2.

3 Red Alert

https://qaofficial.com/post/2019/04/13/69991-3-red-alert.html 2019-04-13
It is very important to maintain connectivity between cities in the war.This topic requires you to write an alarm program that will give a red alarm when the loss of a city causes the country to be divided into several disconnected areas.Note: If the country is not completely connected and is divided into K regions, and the loss of one city does not change the connectivity between other cities, do not issue an alarm.

5-9 Red Alert (25 points)

https://qaofficial.com/post/2019/04/13/69970-5-9-red-alert-25-points.html 2019-04-13
5-9 Red Alert (25 points)It is very important to maintain connectivity between cities in the war.This topic requires you to write an alarm program that will give a red alarm when the loss of a city causes the country to be divided into several disconnected areas.Note: If the country is not completely connected and is divided into K regions, and the loss of one city does not change the connectivity