if-statement

问题 I have to create an object based on a specific situation. I read, that the solution could be the Factory Pattern, but in my case it has a lot of disadvantages. For instance: I have an application that manages animals. At some point a client gives to me a list of animals that must be created. A solution by using the factory pattern should be: //PRODUCTS public interface Animal { String getCall(); } public class Dog implements Animal { public String getCall() { return "Bau"; } } public class

问题 I have to create an object based on a specific situation. I read, that the solution could be the Factory Pattern, but in my case it has a lot of disadvantages. For instance: I have an application that manages animals. At some point a client gives to me a list of animals that must be created. A solution by using the factory pattern should be: //PRODUCTS public interface Animal { String getCall(); } public class Dog implements Animal { public String getCall() { return "Bau"; } } public class

问题 Suppose I have the following column vectors as res1 = -0.81 res2 = 0.61 0.1 -0.4 -0.91 0.62 0.2 -0.56 0.63 -0.72 and I have two fixed constant D = 0.5 . Now suppose an element of res1 is called X and an element of res2 is called Y . I have the following conditions if (X > D && Y < -D) output = 1 elseif (X < -D && Y > D) output = -1 else output = 0 end My question is this: Is it possible to "vectorize" these conditions to iterate over the entire vectors res1 and res2 , such that my output

问题 Suppose I have the following column vectors as res1 = -0.81 res2 = 0.61 0.1 -0.4 -0.91 0.62 0.2 -0.56 0.63 -0.72 and I have two fixed constant D = 0.5 . Now suppose an element of res1 is called X and an element of res2 is called Y . I have the following conditions if (X > D && Y < -D) output = 1 elseif (X < -D && Y > D) output = -1 else output = 0 end My question is this: Is it possible to "vectorize" these conditions to iterate over the entire vectors res1 and res2 , such that my output

问题 One of the stylistic 'conventions' I find slightly irritating in published code, is the use of: if(condition) { instead of (my preference): if (condition) { A slight difference, and probably an unimportant one, but it occurred to me that the first style might be justified if 'if' statements were implemented as a kind of function call. Then I could stop objecting to it. Does anyone know of a programming language where an if statement is implemented as a function call, where the argument is a

问题 I've made a R-Shiny app which runs on a linux server. All the data which I need is coming from a website using API and the library(coinmarketcapr). The app retrieves the latest data every 5 minutes and saves it in a csv-file on the server. But now I have the problem that every time I reload the page, the app retrieves the new data and I always have duplicate values in my time series. I work with the ReactiveTimer, set to 5 minutes. Is there a possibility that the ReactiveTimer checks the time

问题 This question already has an answer here : Console returns undefined [duplicate] (1 answer) Closed 5 years ago . I'm sure I'm just overlooking something, but I can't see what it is. I have a page I'm using to test some new code with using the console. Most of it works. if(typeof(thisNode.L1.download) != 'undefined') { console.log('a1'); if (thisNode.L1.download.sku.toString() == lastSku) { console.log('a2'); addSku = thisNode.L1.cd.sku.toString(); } else { console.log('a3'); } } else if

问题 This question already has an answer here : Console returns undefined [duplicate] (1 answer) Closed 5 years ago . I'm sure I'm just overlooking something, but I can't see what it is. I have a page I'm using to test some new code with using the console. Most of it works. if(typeof(thisNode.L1.download) != 'undefined') { console.log('a1'); if (thisNode.L1.download.sku.toString() == lastSku) { console.log('a2'); addSku = thisNode.L1.cd.sku.toString(); } else { console.log('a3'); } } else if

问题 I am trying to do a check before the data inserts into the MySQL query. Here is the code; $userid = ($vbulletin->userinfo['userid']); $sql3 = mysql_query("SELECT * FROM table WHERE ID='$_POST[hiddenID]'"); while ($row = mysql_fetch_array($sql3)){ $toon = $row['toonname']; $laff = $row['tlaff']; $type = $row['ttype']; if ($type == 1){ $type == "Bear"; } elseif ($type == 2){ $type == "Cat"; } elseif ($type == 3){ $type == "Dog"; } } However, this isn't working. Basically, there are different

问题 I want to check the users input when a new game is created, and see if it is y, n, or neither. For some reason it skips the while loop all together and just outputs "Welcome to Questions." import java.util.Scanner; public class Questions { public static final Scanner INPUT = new Scanner(System.in); private boolean ans; public Questions() { while (ans = false) { System.out.print("Do you want to start a new game (y/n)?: "); String input = INPUT.nextLine(); if (input == "y"){ ans = true; //some