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RX observabl;es only giving one value

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31 Jul 2014 10:25 - 31 Jul 2014 10:26 #2114 by support
I have reproduced the issue. It has to do with the absolute deadband again being used, same as in your previous report.

I was surprised myself to see it behave this way. It looks like that the original design used a different default when this particular overload is used, WITHOUT defaulting to the absolute deadband, which would cause both the examples - in your previous post, and this one - work as you expected.

We will revert the behavior in a future release. Thank you for reporting this.

For now, if - in this particular example - you use the code below instead, it will work:
                UAMonitoredItemChangedObservable<float> dynamic =
                    UAMonitoredItemChangedObservable.Create<float>(
                        new UAMonitoredItemArguments(
                            null, 
                            "opc.tcp://localhost:51210/UA/SampleServer", 
                            "nsu=http://test.org/UA/Data/;i=10853",
                            1000));

Best regards
Last edit: 31 Jul 2014 10:26 by support.
The following user(s) said Thank You: giles

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30 Jul 2014 18:57 #2111 by giles
ps I am uninstalling and reinstalling to make sure it is nothing I have done. I am running on windows 8 btw and the RX DA example works fine. I also tried it out with a node opc server and the server publishes to it and unsubscribes at the end but the observable just doesn't pick anything up except the first ....

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30 Jul 2014 18:29 #2110 by giles
Your UA obbservable example (below) only produces one sample. - surely it should produce a constant stream? The opc node is definitely changing constantly on the server...
// $Header: $
// Copyright (c) CODE Consulting and Development, s.r.o., Plzen. All rights reserved.
 
// ReSharper disable CheckNamespace
// ReSharper disable PossibleNullReferenceException
#region Example
// Shows how to create an observable for OPC-UA monitored item changes, and subscribe to it.
using OpcLabs.EasyOpc.UA.Reactive;
using System;
using System.Threading;
 
namespace ReactiveDocExamples
{
    namespace _UAMonitoredItemChangedObservable
    {
        class Subscribe
        {
            public static void Main()
            {
                Console.WriteLine("Creating observable...");
                UAMonitoredItemChangedObservable<float> dynamic =
                    UAMonitoredItemChangedObservable.Create<float>(
                        "opc.tcp://localhost:51210/UA/SampleServer", "nsu=http://test.org/UA/Data/;i=10853", 1000);
 
                Console.WriteLine("Subscribing...");
                using (dynamic.Subscribe(e => Console.WriteLine(
                    e.Exception == null ? e.AttributeData.ToString() : e.Exception.GetBaseException().ToString())))
                {
                    Console.WriteLine("Waiting for 10 seconds...");
                    Thread.Sleep(10*1000);
 
                    Console.WriteLine("Unsubscribing...");
                }
            }
        }
    }
}
#endregion
// ReSharper restore PossibleNullReferenceException
// ReSharper restore CheckNamespace


and the output =

0) Return
1) "ReactiveDocExamples._DAItemChangedObservable.Subscribe.Main"
2) "ReactiveDocExamples._DAWriteItemValueObserver.OnNext.Main"
3) "ReactiveDocExamples._DAReactive.Composition.Pipeline"
4) "ReactiveDocExamples._UAMonitoredItemChangedObservable.Subscribe.Main"
5) "ReactiveDocExamples._UAReactive.Composition.Pipeline"
6) "ReactiveDocExamples._UAWriteValueObserver.OnNext.Main"
Select action to perform <0>? 4
Creating observable...
Subscribing...
Waiting for 10 seconds...
-2.361808E-31 {System.Single} @30/07/2014 18:25:56 @@30/07/2014 18:25:56; Good
Unsubscribing...
Press Enter to continue...

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