topic Re: How to get a dendrogram to appear in SAS Programming

How to get a dendrogram to appear

rjinks — Wed, 10 Nov 2021 05:04:45 GMT

Dataset 1 will produce a dendrogram, but dataset 2 will not. Why is that, considering the numerical values are the same in both sets?

Set 1

Data PAHcSta;

Input station $ Ace Ant Benzoaa Benzoap Benzobf Benzoghi Benzok Chry Bibenzo Fluora Fluore Indeno Phen Pyr;

datalines;

WR2e1Jy 0 0 0 0 0.0083 0 0 0 0 0 0 0 0.00554 0

WR2e2Jy 0 0 0.00665 0.00665 0.0104 0 0.00475 0.00665 0 0.0152 0 0 0.0076 0.0133

WR2e3Jy 0 0 0.0112 0.0112 0.0168 0.0084 0.0056 0.00933 0.00653 0.0187 0 0.0112 0.0056 0.0187

WR2s3Jn 0 0 0 0.00527 0.0079 0 0 0.00527 0 0.00878 0 0 0.00439 0.00878

WR2s2Jn 0 0 0 0 0.0125 0 0 0.00891 0 0.016 0 0 0.00891 0.016

WR2s1Jn 0 0 0.03 0.045 0.065 0 0 0 0 0.04 0 0 0.03 0.06

;

Proc cluster method=average;

id station;

Run;

Proc tree data=tree;

id station;

Run;

Set 2

Data PAHcSta;

Input station $13 Ace Ant Benzoaa Benzoap Benzobf Benzoghi Benzok Chry Bibenzo Fluora Fluore Indeno Phen Pyr;

datalines;

eWR24sJy 0 0 0 0 0.0083 0 0 0 0 0 0 0 0.00554 0

eWR24sJy 0 0 0.00665 0.00665 0.0104 0 0.00475 0.00665 0 0.0152 0 0 0.0076 0.0133

eWR26sJy 0 0 0.0112 0.0112 0.0168 0.0084 0.0056 0.00933 0.00653 0.0187 0 0.0112 0.0056 0.0187

bWR27saJn 0 0 0 0.00527 0.0079 0 0 0.00527 0 0.00878 0 0 0.00439 0.00878

bWR27sbJn 0 0 0 0 0.0125 0 0 0.00891 0 0.016 0 0 0.00891 0.016

bWR27scJn 0 0 0.03 0.045 0.065 0 0 0 0 0.04 0 0 0.03 0.06

;

Proc cluster method=average;

id station;

Run;

Proc tree data=tree;

id station;

Run;

Re: How to get a dendrogram to appear

Rick_SAS — Wed, 10 Nov 2021 10:38:04 GMT

Your second data set has two rows for which station="eWR24sJy". The row identifiers must be unique. You should see a WARNING In the log that says

WARNING: The DENDROGRAM will not be drawn because the NODEID
values are not unique.

Re: How to get a dendrogram to appear

WarrenKuhfeld — Wed, 10 Nov 2021 11:42:27 GMT

In later versions of SAS, we added dendrograms directly to proc cluster. Do you even need proc tree?

Re: How to get a dendrogram to appear

Rick_SAS — Wed, 10 Nov 2021 11:48:32 GMT

Correct. With ODS GRAPHICS ON, the dendrogram is produced by PROC CLUSTER.

I'll also mention that the second DATA step doesn't seem to work as posted.

One way to fix it is to use a LENGTH statement and remove the $13 token from the INPUT statement:

length station $13;
Input station Ace Ant ...;