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 1:44PM
    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 1:44PM
    I have the same problem.
    What is the version are you using?
  • edited 1:44PM
    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 1:44PM
    afusco wrote: »
    afusco 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.

    I use fastreport 4.9, I have the same problem, Could anyone tell me how to sort it out?
  • edited 1:44PM
    phelps wrote: »
    phelps wrote: »
    phelps 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.

    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.

Leave a Comment

Rich Text Editor. To edit a paragraph's style, hit tab to get to the paragraph menu. From there you will be able to pick one style. Nothing defaults to paragraph. An inline formatting menu will show up when you select text. Hit tab to get into that menu. Some elements, such as rich link embeds, images, loading indicators, and error messages may get inserted into the editor. You may navigate to these using the arrow keys inside of the editor and delete them with the delete or backspace key.