st: Combining strings by group

["Ben Hoen" <bhoen@lbl.gov>]

I can't seem to figure out how to concatenate strings for groups of
variables.

Assume I had the following dataset with two variables:

code	type
1	a
1	c
2	e
3	f
3	g	
3	z

I want to create a third (string) variable that concatenates the string
"type" by code group, which would produce the following output (the quotes
are to indicate a string variable):

code	combinedtype
1	"a, c"
2	"e"
3	"f, g, z"

Therefore for each code group (1, 2 and 3), the type is concatenated with
commas separating each type.

Any ideas?




Ben Hoen
Principal Research Associate
Lawrence Berkeley National Laboratory
Office: 845-758-1896
Cell: 718-812-7589
bhoen@lbl.gov
http://eetd.lbl.gov/ea/emp/staff/hoen.html



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