1 Reply Latest reply: Jun 20, 2012 9:28 AM by Stefan Wühl RSS

    Chart with Letter Expression Values

      Greetings,

       

      I am writing an app to analyze reading levels in a K-12 environment.

       

      My primary issue at the moment is creating a chart with a date as a dimension, and a reading level as an expression.

       

      I can represent this data in tabular form, longitudinally for each student, with no problem:

       

      For a specific student, the tabular data may look like:

       

      Date               Level

      Spring 2011      H

      Fall 2011          K

      Spring 2012      N

       

      When I try to create a chart, there is no data to display. I'm assuming this is because the letters have no context to Qlikview, and as such cannot be ordered in any meaningful way.

       

      If I use some other value that is numeric as the expression, like Reading Accuracy (which is measured as a percentage), the chart works out fine.

       

      Any ideas on a strategy?

       

      Thank you.

        • Re: Chart with Letter Expression Values
          Stefan Wühl

          Try using a dual value as expression result, with the text representation being your Level, and a meaningful numerical representation (maybe your Reading Accuracy) which can be used as numerical input e.g. for bar chart height etc.

           

          dual( Level, [Reading Accuracy] )

           

          edit:

          Or create an inline lookup table where you link your Levels A to Z to numerials as needed:

           

          LOAD * INLINE [

          Level, NumLevel

          A, 1

          B, 2

          C, 3

          D, 4

          E, 5

          F, 6

          ];