4 Replies Latest reply on Mar 26, 2012 10:14 AM by Stephen Huston

    Charting Data That Has Gaps

    ByteTheBullet

      I have a data set that has some values associated with dates. Not every date has a value, however, and I'd like to create a chart that includes those "missing" or "null" values. I suppose another way to describe what I'd like is to have a gapless x-axis, even though some values of X will not have a value for Y. I do not need to "connect" values on either side of a gap, as the fact that there is no value for some dates is important in and of itself.

       

      I'm hoping that there's some method to present a chart such as this without having to specifically create a "zero" record for every date that has no value. Thanks!

        • 1. Re: Charting Data That Has Gaps
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          ByteTheBullet wrote:

           

          I'm hoping that there's some method to present a chart such as this without having to specifically create a "zero"  record for every date that has no value. Thanks!

           

          You cannot chart data that you don't have. So even if you don't create a record for each missing date, you must provide the chart with a value for each X-axis point, and the Y-axis values need to correspond to the provided X-axis points.

          • 2. Re: Charting Data That Has Gaps
            Stephen Huston

            And keep in mind that "dates" are just one form of "data" to FileMaker. It doesn't know that a date is missing from data just because the previous data is more than 1 (one) different from the next record. You will need to test either previous or next record via a calc to determine if something is missing and then decide how to deal with that.

             

            Generally, data points represent records, so you are likely to need the dummy/zero record in the set for it to chart.

            • 3. Re: Charting Data That Has Gaps
              comment

              Stephen Huston wrote:

               

              Generally, data points represent records

               

              I wouldn't say that.

               

              In any case, inserting dummy records into your "real" data table just for the purpose of charting seems like a very bad idea to me.

              • 4. Re: Charting Data That Has Gaps
                Stephen Huston

                I didn't say it was a good idea. I also suggested handling the gaps if detected. This might be done with calculations, but adding calc fields to fill record gaps is even a heavier load on the table than dummy records, and it's harder to chart.

                 

                I am not suggesting there is a good way to chart missing data. Just pointing out that something must be added to the system if one insists on charting data that isn't already there.