python data analysis

python data analysis (2) This part is also a practical case. I have read Python foundation and python data analysis for many times, but I still feel a bit empty if I don't really knock code. Recently, I am constantly looking for cases and constantly knock code myself. Case link: https://segmentfault.c ...

Posted on Mon, 29 Jun 2020 05:24:16 -0400 by alant

Fast Fourier transform (FFT)

polynomial Coefficient representation If \ (f(x) \) is a \ (n-1 \) degree polynomial, then \ (f(x)=\sum\limits_{i=0}^{n-1}a_i*x^i\) Where \ (a_i \) is the coefficient of \ (f(x) \), and the complexity of this method is \ (O(n^2) \) Point value representation According to the knowledge of elementary school, a polynomial of degree (n-1) ca ...

Posted on Mon, 29 Jun 2020 04:04:11 -0400 by Wade

Experiment 2 goods purchase and sale management system

Write a Inventory.java Complete the following functions: 1. The program first opens and reads Inventory.txt All inventory records recorded in and read Transactions.txt , process the transactions contained in this file, and record the delivery records to Shipping.txt , and record the error message to Err ...

Posted on Sat, 27 Jun 2020 05:27:11 -0400 by utherwun

The solution of lock in Java

1. Optimistic lock and pessimistic lock Optimistic locks and pessimistic locks should be the first two types of locks that every developer contacts. Application scenarios are mainly used to update data, which is also one of the most important scenarios for using locks. The main process of updating d ...

Posted on Sat, 27 Jun 2020 04:21:02 -0400 by phpbaby2009

PAT 1052 (20 points)

1052 selling cute (20 points) Cute emoticons are usually composed of three parts: hand, eye and mouth. For simplicity, let's assume that an emoticon is output in the following format: [left hand] ([left eye] [mouth] [right eye]) [right hand] Now we give the optional symbol set. Please output the expr ...

Posted on Sat, 27 Jun 2020 03:41:07 -0400 by programmermatt

C ා 9.0 finally comes, top level programs and Partial Methods two new features explore

1: Background 1. Story telling . NET 5 finally released the sixth preview version on June 25, with more new features added to the C ා 9 preview. This series can also continue to write. There is no more nonsense. Today, let's take a look at the top level programs and Extending Partial Methods. 2. Necessary for installation Download the latest. ...

Posted on Sat, 27 Jun 2020 01:02:58 -0400 by mmitdnn

Data structure big job space and text query efficiency analysis

Article catalog preface Task 1 merchant location point query Topic Thinking design Implementation code hash_(sequential / binary)_search Binary_search_tree Data analysis Task 2 t o p − k top-k top − K merchant query Question surface Thinking design Implementation code Book s ...

Posted on Sat, 27 Jun 2020 00:03:02 -0400 by 2DaysAway

UnityStandardAsset project, source code analysis_ 4_ Racing game [AI control]_ AI mechanism

Address of the previous chapter: UnityStandardAsset project, source code analysis_ 4_ Racing game [player control]_ Camera control In the previous chapters, we have analyzed most of the mechanisms of racing games, and Unity also provides different control modes - AI control. As its name implies, AI is u ...

Posted on Fri, 26 Jun 2020 23:41:23 -0400 by dotbob

Two common applications of linear structure queue (with implementation code)

Two common applications of linear structure 1. Definition A storage structure that can realize FIFO 2. Classification (1) Chained queue -- realized by chained list (2) Static queue -- implemented by array Static queues usually have to be circular queues 3. Loop queue (1) Why static queues ...

Posted on Fri, 26 Jun 2020 23:07:19 -0400 by macewan

Spring Source Series--Source Analysis of bean Components

brief introduction The spring-bean component is the core of Spring IoC. We can use its beanFactory to get the objects we need. The instantiation, property assembly and initialization of objects can be handed over to Spring for management.This article will start with DefaulTListableBeanFactory.getBeanThe (Class) method begins the analysis of th ...

Posted on Fri, 26 Jun 2020 20:20:47 -0400 by january_9th