Filtering list based on instance type

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• Nested list in C# with layers

  I am not an expert coder and I have just started learning about Generic data types. What I am trying to code is a List inside of a list inside of a list .

  For example- at the first level - I want numbers each inside of a list

  Layer 1 list1=[1,2,3,4,5,6,7,8,9,10......1000] ,

  At the 2nd layer I'd like list from 1st layer added as an element to a parent list 2 when layer 1 meets certain condition- ex layer 1 reaches max=10

  List2=[List1[0:10],List1[10:20],List1[20:30], .....] ,

  At layer 3, i'd like to repeat the process, all elements of layer 2 get added as an element to a new parent list 3 when layer 2 meets a max condition. list3[0]=[list2[0:10],list2[10:20],list2[20:30]..... and so on.

  Only the first layer would have integer values, the successive layer would be a wrapping of it's the previous layer. How can I code this in C#?

  Thanks!
• python list ofwords.the program outputsthosewords&theirfrequencies.Ex:if the input is:hey hi Mark hi mark the output is: hey 1 hi 2 Mark 2 hi 2 mark 2

  I thought I could use this code:

  wordInput = input()
  
  myList = wordInput.split(" ")
  
  for i in myList:
  
     print(i,myList.count(i))
  

  but its output is:

  hey 1
  Hi 1
  Mark 1
  hi 1
  mark 1
  

  How can I make it:

  Hey 1
  Hi 2
  Mark 2
  hi 2
  mark 2
  
• How to convert DataTable to List<T> in C#

  For convert DataTable to List you can used the AutoMapper Library and you can do it automatically
• Updating a Single Column In Room Database

  That's the function I'm using for updat

  private fun updateSettingsDatabase(settingsDao: SettingsDao) {
          lifecycleScope.launch {
              settingsDao.update(SettingsEntity(
                  1,
                  nightMode=nightModeResult,
              ))
          }
  }
  
  @Query("SELECT * FROM `settings-table`")
  fun fetchCurrentSettings(): Flow<List<SettingsEntity>>
  

  I specified nightMode= because I thought that this way I'm only updating this colummn, but it turns out that it resets every column, how do I update a single column, while keeping the values the rest of the columns?
• Kotlin Coroutines Unit Testing

  Im trying to test this suspend function:

  suspend fun <T> getResult(call: suspend () -> Response<T>): Resource<T> {
  
    val response = call()
    val body = response.body()
    val code = response.code()
  
    if (response.isSuccessful) {
  
      Log.d(Cybrid.instance.tag, "Data: ${response.code()} - ${response.body()}")
      return Resource.success(body!!, code)
  
    } else if (response.code() == HTTP_UNAUTHORIZED || response.code() == HTTP_FORBIDDEN) {
  
      Cybrid.instance.let { cybrid ->
        cybrid.listener.let {
          cybrid.invalidToken = true
          it?.onTokenExpired()
        }
      }
      Log.e(Cybrid.instance.tag, "Error - Something wrong with TOKEN : ${response.code()} ${response.message()}")
      return Resource.error(response.message(), code=response.code())
    } else {
      Log.e(Cybrid.instance.tag, "Error - Other: ${response.code()} ${response.message()} :: ${response.raw()}")
      return Resource.error(message = response.message(), data= response.body(), code= response.code())
    }
  }
  

  With this Unit Test Case, all it cover except line 13 , I dont know how to cover the line!!!

  @ExperimentalCoroutinesApi
  @Test
  fun get400ErrorServerTest() = runBlocking {
  
      Cybrid.instance.setBearer("Bearer")
      val pricesService = AppModule.getClient().createService(PricesApi::class.java)
      val result = getResult { pricesService.listPrices() }
  
      Assert.assertNotNull(result)
      Assert.assertEquals(result.code, 400)
      Assert.assertNull(result.data)
  }
  

  The coverage report says:

  

  Some idea to get coverage for line 13 ??? Thnanks
• Android ZoneDateTime.withHour always sets hour to 8

  So I am tring to schedule alarm at a particular time on current day using AlarmManager. To do that I am using ZoneDateTime to get current time and then updating it to the hour at which I need to set the alarm. But for some reason time.withHour is giving me 8pm or 8am no matter what hour I am passing to it. Am I doing something wrong here?

  var time = ZonedDateTime.now()    //getting current time at my timezone
  time = time.withHour(22).withMinute(8).withSecond(0)
  print(time)                       //getting 8am/8pm at my timezone
  val timeMilis = time.toInstant().toEpochMilli()
  
• rsyslog property filter by expression not working

  I want to filter the rsyslog message by the expression. when I send the message over the udp socket, the filter works as expected. But when sending the message over the UNIX socket, the filter does not work?

  if ($syslogtag == 'nginx:') then {
  action(type="omfwd" target="192.168.56.133" protocol="tcp" port="514"
         StreamDriver="gtls" StreamDriverMode="1" StreamDriverAuthMode="anon"
         queue.filename="forwarding" queue.spoolDirectory="/var/log"
         queue.size="10000" queue.type="LinkedList" queue.maxFileSize="1g" queue.SaveOnShutdown="on"
         action.resumeRetryCount="-1")
         & stop
  }
  
• If statements within a Query

  I'm using a query & importrange combo like this:

  =IFERROR(QUERY(IMPORTRANGE("https://docs.google.com/spreadsheets/d/1EizWsVwZfUy1NDRwmmWEpj2OxTGvBjP9-YBbds9xmr0/edit#gid=0", "'Locations'!A2:C"), "select Col3 where Col1='"&J4&"' and Col1<>''"))
  

  But Instead of just searching column 1 and returning the associated value in column 3, I would like it to return the associated value in:
  Col3 if the value is in Col1
  Col7 if the value is in Col5
  Col11 if the value is in Col9
  

  It can throw an error if the value is in more than one place, or return the result at the first occurrence, either way is fine.

  I'm trying to do this using "countif" within the query but am not having a much luck.
• Python: extracting specific values out an numpy array of indices

  I have a numpy array of indices. For example:

   indices = np.array([0, 1, 2, 6, 7, 9, 12, 13, 14])
  

  I would like to make an array

  signals = np.zeros(np.amax(indices) + 1)
  

  where I put a value of 2.0 for the beginning index of a sequence of the form: 0, 1, 2, 3 or 8, 9, 10, 11 (so where the value increases 1) and the last element of this sequence to be 3.0.

  If the sequence is only a single number long (so no sequence) I would put the value 4.0 in this array.

  So for the example given above the output should be [2.0, 0, 3.0, 0, 0, 0, 2.0, 3.0, 0, 4.0, 0, 0, 2.0, 0, 3.0].
• Will volatile work for Collections and objects?

  Trying to understand the theory about volatile. They say, volatile provides happens-before, so changes done in thread 1 should be visible in thread 2.

  What if we will put volatile for Collection? Will java provide visibility in Thread 2 for changes done in Thread 1 ? And why?

  public class Vol {
      volatile List<String> list = new ArrayList<>();
      
      // thread 1
      public void put(String s) {
          list.add(s);
      }
      
      // thread 2
      public List<String> get(){ // all changes are visible? "Why" for No\Yes answer
          return list;
      }
  }
  
• storing the HashMap key value pair by code refactoring

  I am trying to refactor the below method and return Map<Integer, List<OrderReference>> response = new HashMap<>(); instead of Map<DepartmentReference, Integer> I want to store the error number we are currently storing as value in the below method as key in the new refactored method and value will be List<OrderReference>

  private Map<DepartmentReference, Integer> getBulkOrders(String type, List<BulkSpecification> bulkSpec) {
          Map<DepartmentReference, Integer> departmentOrders = new HashMap<>();
          for (BulkSpecification bulkSpecification : bulkSpec) {
              List<Order> orders = new ArrayList<>();
              List<OrderReference> ordRefs = bulkSpecification.getOrderReferences();
              for (OrderReference ordRef : ordRefs) {
                  Order order = new Order();
                  order.setSpecification(bulkSpecification.getSpecification());
                  DepartmentReference departmentReference = OrderPersist.getDealerInformation(ordRef.getVistaReference());
                  order.setOrderReference(ordRef);
  
                  if (!Order.validateOrder(order, type)) {
                      departmentOrders.put(departmentReference, 3);
                  } else {
                      OrderPersist orderPersist = new OrderPersist();
                      try {
                          MyOrderResponse myOrderResponse =
                                  orderPersist.bulkorderer(order, getUserCode(),
                                          getMessage(getMarket(), getLanguage(),
                                                  4), type);
                          if (myOrderResponse.getUpdateStatus().isSuccessful()) {
                              departmentOrders.put(departmentReference, 0);
                              orders.add(order);
                          } else {
                              departmentOrders.put(departmentReference,
                                      6);
                          }
                      } catch (OrderError orderError) {
                          Exception exception = orderError.getOrderException();
                          int errorNo = 10;
                          if (exception != null
                                  && exception instanceof SQLException
                                  && ((SQLException) exception).getErrorCode() == GENERIC_SQL_ERRNO) {
                              errorNo = 1178;
                          }
                          departmentOrders.put(departmentReference,
                                  errorNo);
                      }
                  }
              }
          }
          return departmentOrders;
      }
  
• Kotlin Collection indexOf using reference equality ===

  In Kotlin, indexOf(x) called on a Collection returns the index of the first element that equals(x) (structural equality ==)

  How can one get the index based on referential equality (===) instead?
• Binary tree not clearing with each loop iteration

  I am using a binary tree to convert prefix expression into infix, and then solving them. That part works fully.

  My issue is the input loop I set up is adding on the new expression to the old tree, resulting in an error. I have tried clearing the linked list, and manually created a method to empty out the tree. But every time, the output I have is showing the new expression appended to the previous one, rather than creating a whole new tree.

      public static void main(final String[] args) {
          Scanner listener = new Scanner(System.in);
          System.out.println();
          System.out.println("Enter a prefix expression Separated by space!! (Enter 'done' to end): ");
          String line = listener.nextLine();
          while(!line.equalsIgnoreCase("done")){
          System.out.println(line);
              if(line.length()<=1){ System.out.println("Invalid expression"); listener.close(); return;}
  
              instances(line);
              line =  new String();
              line = listener.nextLine();
          }
          listener.close();
      }
      public static void instances(String input){
          System.out.println("The input expression was \n\t"+ input +"\n");
          String[] in = input.split(" ");
          LinkedList<String> queue = new LinkedList<>(Arrays.asList(in));
          TreeNode root = new TreeNode(queue, null);
          System.out.println("Expression as infix: ");
          inOrder(root);
          System.out.println(infix_string);
          String[] infix = infix_string.split(" ");
          Stack infix_stack = new Stack(infix);
          System.out.print("\t" + infix_stack + " = ");
          infix_stack.answer();
          System.out.println();
          System.out.println("Enter a prefix expression Separated by space!! (Enter 'done' to end): ");
          queue.clear();
          clearTree(root);
      }
  
      public static void clearTree(TreeNode root){
          if(root != null){
              clearTree(root.left);
              clearTree(root.right);
              root=null;
          }
      }
  }
  

  
• Pythonic way to declare instance variables

  Let's say that in my __init__ I'm performing certain operations on variables that I declare. Those variables will be used by the other class methods.

  What is more pythonic:

  def __init__(self, a, b):
    c = a + b
    d = c ** 2
    self.c = c
    self.d = d
  

  or

  def __init__(self, a, b):
    self.c = a + b
    self.d = self.c ** 2