Line Charts and Null Values

I am currently evaluating Fast Reports as a replacement for Crystal Reports using Delphi 2009. One of our reports has 2 line charts, each with 2 line data series. It is important that any null values do NOT graph. I see a TreatNulls property and I've set it to every possible value (tnIgnore, tnSkip, tnDontPaint) but the null values show up on the graph as a 0 - not good. Is this a bug or am I doing something wrong?

Also I would like to make a custom label for the y-axis that doesn't use the values in the data series (e.g. instead of showing -10 I would like the label to say 'Low").

Thanks.

Comments

  • edited 5:33AM
    afusco wrote: »
    I am currently evaluating Fast Reports as a replacement for Crystal Reports using Delphi 2009. One of our reports has 2 line charts, each with 2 line data series. It is important that any null values do NOT graph. I see a TreatNulls property and I've set it to every possible value (tnIgnore, tnSkip, tnDontPaint) but the null values show up on the graph as a 0 - not good. Is this a bug or am I doing something wrong?

    Also I would like to make a custom label for the y-axis that doesn't use the values in the data series (e.g. instead of showing -10 I would like the label to say 'Low").

    Thanks.

    I found a some potential solutions. Even though the TreatNulls property was set ok and nulls were being returned from the database I needed to set frxReport.EnginOptions.ConvertNulls to False. This prevents any null value from being graphed but I am still having a bit of a problem. I need the x-axis to show ALL labels ALL of the time regardless of whether there is a data point at that value. For instance the x-label is 500,1000,2000,3000,4000,6000 & 8000. Those values always need to be displayed. Yet if the 8000 data point is NULL the 8000 x-label will not show. It will just be blank. How do I fix this?

    Also, what is the difference betwee the 3 TreatNulls properties (tnIgnore, tnSkip, tnDontPaint)?

    Thanks.
  • edited 5:33AM
    I have the same problem.
    What is the version are you using?
  • edited 5:33AM
    fbonis wrote: »
    I have the same problem.
    What is the version are you using?
    I am using the stable 4.8 version and I still don't have a solution to the problem.
  • edited 5:33AM
    afusco wrote: »
    I am using the stable 4.8 version and I still don't have a solution to the problem.

    I use fastreport 4.9, I have the same problem, Could anyone tell me how to sort it out?
  • edited 5:33AM
    phelps wrote: »

    I use fastreport 4.9, I have the same problem, Could anyone tell me how to sort it out?

    I solved this problem, You need to set TfrxChartView.IgnoreNulls=True, TfrxReport.EngineOptions.ConvertNulls=False.

    It Works well.

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