while-loop

问题 This is my code : #Choose Report def chooseReport(): print "Choose a report." while True: choice = raw_input("Enter A or B: ") if choice == 'a' or choice == 'A': reportA() break elif choice == 'b' or choice == 'B': reportB() break else: continue When I input either a or b , it just asks me to "Enter A or B" again. It doesn't go to the functions its supposed to. Any idea why is this? 回答1: The code is perfect, except a redundant else, as mentioned in the comment. Are you entering a (a + space)

问题 In my code, I have a vector <vector <vector <vector <std::tr1::shared_ptr<foo> > > > > named foosBoxes . The nested vector has a role of simulating a physical boxes position. I also have a while loop which cause a segmentation fault: vector<std::tr1::shared_ptr<foo> >::iterator fooit = foosBoxes[x][y][z].begin(); //x,y,z are valid integer std::tr1::shared_ptr<foo> aFoo; while (fooit != foosBoxes[x][y][z].end()){ aFoo = *fooit; //this cause segmentation fault fooit++; //some stuff which does

问题 Basically I have two while loops in my code. All they do is count in increments of 1 from 0 to either 10 or -10. The vectors that count are "count1" and "count2". This is happening in my code in two separate while loops. However, I now need each count dependent on each other so I need them within the same loop. Is it possible to have the two separate while conditions working in one loop. For example, what I have now is: count1 = 0 count2 = 0 l_RWM = vector() r_RWM = vector() while (count1 <

问题 I'm working on a huge SQL code and unfortunately it has a CURSOR which handles another two nested CURSORS within it (totally three cursors inside a stored procedure), which handles millions of data to be DELETE,UPDATE and INSERT. This takes a whole lot of time because of row by row execution and I wish to modify this in to SET based approach From many articles it shows use of CURSORs is not recommend and the alternate is to use WHILE loops instead, So I tried and replaced the three CUROSRs

问题 For a web-scraping analysis I need two loops that run permanently, one returning a list with websites updated every x minutes, while the other one analyses the sites (old an new ones) every y seconds. This is the code construction that exemplifies, what I am trying to do, but it doesn't work: Code has been edited to incorporate answers and my research from multiprocessing import Process import time, random from threading import Lock from collections import deque class MyQueue(object): def _

问题 So for my program I need to check a client on my local network, which has a Flask server running. This Flask server is returning a number that is able to change. Now to retrieve that value, I use the requests library and BeautifulSoup. I want to use the retrieved value in another part of my script (while continuously checking the other client). For this I thought I could use the threading module. The problem is, however, that the thread only returns it's values when it's done with the loop,

问题 this is my piece of code: // TODO Auto-generated method stub try { Socket clientSocket = new Socket("localhost", 8888); ObjectOutputStream ous = new ObjectOutputStream(clientSocket.getOutputStream()); while(sending) { Statistics statsData = setStatisticsData(); ous.writeObject(statsData); Thread.sleep(5000); } } catch(UnknownHostException uhe) { uhe.printStackTrace(); } catch(IOException ioe) { ioe.printStackTrace(); } catch (InterruptedException e) { // TODO Auto-generated catch block e

问题 I want to make a vector using a loop. Here's my R code: vec_teamCodes <- c() x <- 0 while (x < 10) { append(vec_teamCodes,"Hello") x <- x+1 } But when I run it, vec_teamCodes() remains NULL . Why? How do I fix my code? 回答1: Try this: vec_teamCodes <- c() x <- 0 while (x < 10) { vec_teamCodes <- c(vec_teamCodes,"Hello") # OR # vec_teamCodes <- append(vec_teamCodes,"Hello") x <- x+1 } [1] "Hello" "Hello" "Hello" "Hello" "Hello" "Hello" "Hello" "Hello" "Hello" "Hello" 来源： https://stackoverflow

问题 Ths is a question from a past paper. I have been asked to create a static method arrayMin to find the smallest value in the array arr . I have to use a while loop and on each iteration, the variable min will return the smallest number from the first i elements. Is there a way to do this without calling another method/for loop and strictly using the while loop, as the question is only worth 4%(including writing loop invariants and javadoc). Not sure if I am overcomplicating the problem. public

问题 i am trying to implement multidimentional lstm in tensorflow, I am using TensorArray to remember previous states, i am using a complicated way to get two neigbours state(above and from left). tf.cond want that both posible condition to exist and to have the same number of inputs. this is why i added one more cell.zero_state to the (last index +1) of the states. then i using a function to get the correct indexes to the states. when i am trying to use an optimizer in order to minimize a cost, i