topic Re: How to force equal bin size in grouped histogram in ODS and Base Reporting

How to force equal bin size in grouped histogram

Ullsokk — Thu, 17 Jan 2019 13:37:04 GMT

I have a report that dynamically compares two groups distribution on the most relevant variables.

 ods graphics / NBINSMAX=100;

proc sgplot data=combo ;
  histogram &var._1 / fillattrs=graphdata1 name='s' legendlabel='Group 1 transparency=0.5 ;
  histogram &var._0 / fillattrs=graphdata2 name='d' legendlabel='Group 2' transparency=0.5 ;
  keylegend 's' 'd' / location=inside position=topright across=1;
  xaxis display=(nolabel);
  run;

I want max 100 bins, but I want both groups to have the same number of bins, so that it is easy to compare the distributions. With the following code, the two distributions can get wildy different bin sizes, as shown in the example below.

As this is part of a macro, I cannot set the bin size manually for each plot, and just want each plot to have a uniform bin size for each group.

Re: How to force equal bin size in grouped histogram

PaigeMiller — Thu, 17 Jan 2019 13:52:21 GMT

Use the BINWIDTH= option of the HISTOGRAM command.

Also, use one HISTOGRAM statement with a GROUP= option.

Also consider using the DENSITY command instead of the HISTOGRAM command.

Re: How to force equal bin size in grouped histogram

Ullsokk — Thu, 17 Jan 2019 13:52:37 GMT

I really want to use proc sgplot, are you sure grouping is possible? Cant find example code for this in sgplot.

As for setting the binwidt, as I stated, I cant set this manually, as this is a macro that needs to show a sensible plot for any input data

Re: How to force equal bin size in grouped histogram

PaigeMiller — Thu, 17 Jan 2019 13:56:29 GMT

@Ullsokk wrote:

I really want to use proc sgplot, are you sure grouping is possible? Cant find example code for this in sgplot.

Yes

https://documentation.sas.com/?cdcId=pgmmvacdc&cdcVersion=9.4&docsetId=grstatproc&docsetTarget=n0p7vdd69sgf3wn1479qxqxuryrt.htm&locale=en#n12ydifq7odra9n16dvrvz15klzjd

As for setting the binwidt, as I stated, I cant set this manually, as this is a macro that needs to show a sensible plot for any input data

If you are writing a general macro, you will know from the data the min and max values of the data, and so if you want k bins, you can figure out the width of each one of the k bins.

Re: How to force equal bin size in grouped histogram

Ullsokk — Thu, 17 Jan 2019 14:03:17 GMT

I have no idea how I missed that, thanks a bunch

Re: How to force equal bin size in grouped histogram

PaigeMiller — Thu, 17 Jan 2019 14:11:33 GMT

And consider using the DENSITY command instead of the HISTOGRAM command.