
1. Re: Why cant I use a histogram ie bin the Measure , when it is a calculated field , or make the calculated field a dimension. When you right click on the field it does not allow the bin option , nor can I drag it up / convert to a dimension.
Tracy Rodgers Jul 30, 2012 3:00 PM (in response to Graham Bortz)Hi Graham,
Are you able to post the workbook (twbx file)? Or if not, perhaps give us the formulas that you are using?
Tracy

2. Re: Why cant I use a histogram ie bin the Measure , when it is a calculated field , or make the calculated field a dimension. When you right click on the field it does not allow the bin option , nor can I drag it up / convert to a dimension.
Graham Bortz Aug 1, 2012 3:59 AM (in response to Tracy Rodgers)Hi Tracy,
I have developed a sheet with a much simpler application of my problem. Basically I am trying to get a distribution of a calculated field.
The application provided in the sheet is about onnet ( calling to other subs on your own network) and offnet ( calling to other networks) calling on cell sites and the ratio of onnet to offnet calls. The cell sites are segmented ( s1 to s3 ) and are in certain regions. We can therefore aggregate cells into segments and/or regions and get the On/off ratios of the segments and or regions by using a sum function in the Calculated field to avoid additions of ratios ( WHICH IS WRONG!!!)
In the one histogram I plot the ratio which is calculated for each site in the spreadsheet. This is fine as long as you dont combine cell sites in categories. As soon as you do this , it adds the ratios in the categories ( Hist Ratio Sum sheet) , which is not the same as calculating the sum of onnet and offnet durations and then dividing those totals , which I do in the sheet Dist of Ratio's..here I plot the correct ratio but in bins of the original onnet ratios I calculated in the sheets.
What I actually want to do is plot the count of the calculated field ratios , in bins of calculated field ratios , a normal calculated field histogram. I would then put the segment categories in colour in the histogram.
So I prepared a table showing a region split of the segments ( s1  s3 ) and the Calculated Field ratios of the Onnet to Offnet calling dropped into the text . "see Table of Calc Field sheet". I now wish to get a distribution of the numeric field , which is a distribution of a calculated field.
I attach a presentation showing that binning is not possible in a calculated field using the Sum in the calculation and the w/book . At a Seminar in South Africa, Terry ( from Tableau ) said that because the Calculated field becomes an Aggregate when I use the Sum function , you cant bin aggregates. He mentioned that a way round it is to make an "extract ??" of the data ... I suppose he meant of my "TABLE of Calc Field" Sheet and do the binning on the extract. If this is the case can you show me how. Although it does the job , I am not sure if the extract is live ( dynamic) , and if I will have to do a new extract everytime I slice and dice the data ie I cant do by point and click anymore. Is there a more innovative way round it?
Many thanks again for your interest in my problem. It crops up time and time again in my work and I have to plot the histograms manually outside tableau.
Regards
Graham

Onnet_Offnet.twbx.zip 50.9 KB
