• ## Math class

Time：2021-10-17

summary Java.lang.math class package, which executes basic mathematical operation methods method Return absolute valuedouble s = Math.ceil(-5);//5 The integer becomes larger and the negative becomes smallerdouble d2 = Math.ceil(3.5);//4 The integer becomes smaller and the negative becomes larger double d3 =Math.floor(3.5);//3 roundingdouble d4 =Math.round(4.5);//5

• ## If you don’t want to be called Bao Xia, please learn machine learning algorithms effectively

Time：2021-10-5

Machine learning goes far beyond the simple fit and predict methods in sklearn. Background: Now everyone is used to saying the word “switchman”, especially in the field of artificial intelligence. One of my friends laughed at me and said:“What have you learned so long? Just a few models. I learned them in a week。”   […]

• ## Five commands for using calculator in Linux command line

Time：2021-10-4

When using Linux, we sometimes need to do some calculations, so we may need to use calculators. In the Linux command line, there are many calculator tools. These command line calculators can let us perform scientific calculations, financial calculations or some simple calculations. Of course, we can also use these commands in shell scripts to […]

• ## Online PI query download tool

Time：2021-9-26

Online PI query download tool Online PI query download tool PI (PI) is the ratio of the circumference of a circle to its diameter. It is generally expressed by the Greek letter π. It is a common mathematical constant in mathematics and physics. π is also equal to the ratio of the area of the […]

• ## Wavy line (~) in latex, greater than or equal to

Time：2021-9-7

Wavy line ～ For wave line in latex\simWrite it out, as shown in the figure below: 5\sim~ Greater than or equal to Greater than or equal to (\ GEQ) in latex\geqWrite it out, as shown in the figure below: n\geq2 Mathematical symbols This work adoptsCC agreement, reprint must indicate the author and the link to […]

• ## In latex φ Writing method

Time：2021-9-6

φ In latex φ use\varphiAs shown in the figure below: \varphi Mathematical symbols This work adoptsCC agreement, reprint must indicate the author and the link to this article Hacking

• ## Matrix writing in latex

Time：2021-9-5

matrix The first method is to write in matrix, pMatrix, bMatrix, bMatrix, vmatrix or vmatrix environmentFor example,1. \begin{matrix} 0 & 1 \\ 1 & 0 \end{matrix} As shown in the figure below:2. \begin{bmatrix} 0 & -i \\ i & 0 \end{bmatrix} Mathematical symbols This work adoptsCC agreement, reprint must indicate the author and the link […]

• ## Problems of summation symbols and arrows in latex

Time：2021-9-3

Summation symbol Sum in latex (\ sum {}) For symbols\sum_{ Sum lower limit} ^ {sum upper limit}Write it out, as shown in the figure below: \displaystyle \sum_{i=1}^{N} Note: don’t forget to write\displaystyleOtherwise, the following effect will appear: \sum_{i=1}^{N} arrow Arrow in latex \ rightarrow\rightarrowWrite it out, as shown in the figure below: \rightarrow Mathematical symbols […]

• ## Existence in latex, arbitrary, ξ Symbol

Time：2021-8-31

Existential symbol The \ exists symbol in latex\exists, as shown in the figure below: \exists d Arbitrary symbol \ forall symbol in latex\forall, as shown in the figure below: \forall \Xi symbolUse \ Xi symbol in latex\xi, as shown in the figure below: \xi Mathematical symbols This work adoptsCC agreement, reprint must indicate the author […]

• ## C + + Basics: C + + numbers

Time：2021-8-24

Usually, when we need to use numbers, we will use the original data types, such as int, short, long, float, double and so on. These data types for numbers, their possible values and numerical ranges, have been discussed in the chapter of C + + data types. C + + define numbers We have […]

• ## Vue forces component re rendering

Time：2021-7-1

In Vue, we may have many businesses referring to a component for instance For example, there are 10 different types of tab problems in mathematics, but they refer to a common componentAt this time, when we switch the tab, we will report an error in the name value of the component, or the component has […]

• ## Lambda expression of Python

Time：2021-6-28

The article was first published in:https://mp.weixin.qq.com/s/pZNziOlKYcibqQ5X_LhPqw What is a lambda expression Lambda expression is an anonymous function. Lambda expression is based on mathematics λ It is an anonymous function, that is, a function without a function name. Lambda expressions can represent closures (note the difference from the traditional mathematical sense).Is a quick definition of a […]