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Doing %o% that operates on columns instead of atomics

Ken-JP 
Okay, this one is hard to put into words:
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What I would like to do is apply my.foo() which takes two columns, a and b,
does an operation and returns another column c.  The columns I want to feed
into my.foo() are all the combinations of columns in y.  So I want to apply
my.foo( y[,1], y[,1] ) and then my.foo( y[,1], y[,2] ), etc...  for all
combinations() of the 10 columns in y.

I would expect the final output to be 10x10x10.  Passing 10 columns by 10
columns to my.foo() which outputs a vector of 10 numbers at a time.

***So in essence, what I am trying to accomplish is like outer(), but
instead of operating on atomic values, I want to operate on columns of y.

I know I can use loops to accomplish this, but I would like to code as
R-like as possible.  I am learning a great deal about "how to think in R"
from the excellent replies on this board.

Thanks in advance for any suggestions.

Thread (4 messages)

Ken-JP Doing %o% that operates on columns instead of atomics Mar 25 Ken-JP Doing %o% that operates on columns instead of atomics Mar 25 Stavros Macrakis Doing %o% that operates on columns instead of atomics Mar 25 jim holtman Doing %o% that operates on columns instead of atomics Mar 25