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The complete message is: Unsorted data occurs in the collection. The only allowed SearchMode is Exact when FindIndex() is called on an unsorted collection, but Nearest was passed in.

I started with three renderable series that all had a certain time scale (x axis). I want to add another renderable series but it uses a separate time scale (x axis). I received this error so I put the two lists (x axis and y axis data) into a dictionary and used orderby on the dictionary key (time scale x axis list). I then cleared and appended this data to my DataSeries property. The code is still throwing this exception. What does unsorted mean?


Edit: The data is ordered by the key (timespan) in ascending order before I use orderby.

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Hi Ryan,

This post explains why SciChart prefers sorted data, and what steps you can take to allow unsorted data by enabling this property here.

If you’re 100% sure you have data sorted in X (have output to console window and checked it), then you may have come across a bug. In that case, let us know the conditions to recreate the bug and we will investigate as soon as possible.

Best regards,

  • Andrew
    I have no idea I’m afraid, but if you can recreate we can debug it and get to the bottom of the issue.
  • Ryan Woods
    I figured it out! It was a silly mistake. As I was playing around with the values and learning about the different kinds of renderable series, I didn’t use the proper XyDataSeries property for the Append action.Thanks for your time!
  • Andrew
    That’s great! Glad you are sorted. Yes, the exceptions for unsorted data here are specifically designed to warn users if they have *accidentally* appended data unsorted in X. Intentional is fine if you set the DataSeries.AcceptsUnsortedData flag, just ideally you want the full power of scichart when your data ascends in X right?
  • Ryan Woods
    Well, it is a confusing error to say the least. It tells me that the data is unsorted, but it is very clearly sorted. The issue was that, by appending a new data set to the series, it would throw an exception. It might have been that when I appended the new dataset to the dataseries, it found a conflict where the xaml for dataseries 1 and 2 were both bound to a certain x and y axis but they had different sets of data. i.e. the x values were different and it didn’t know how to handle that on the same x axis.What do you think?
  • Ryan Woods
    I understand it. I thought about it a moment… I didn’t clear the data so while both data sets were ordered, appending one to another was not!Thanks again!
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