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From: Matthias Boehm <mboehm7@googlemail.com>
Subject: Re: Table
To: dev@systemml.incubator.apache.org
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Date: Fri, 21 Apr 2017 11:47:23 -0700
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archived-at: Fri, 21 Apr 2017 18:47:30 -0000

The input vectors to table are interpreted as row indexes and column 
indexes, respectively. Without weights, we add 1, otherwise the 
corresponding weight value to the output cells.

So in your example you have constant row indexes of 1 but a seq(1,10) 
for column indexes and hence you get a 1x10 output matrix.


Regards,
Matthias

On 4/21/2017 4:00 AM, arijit chakraborty wrote:
> Hi,
>
>
> I was trying to understand what the "table" function does. In the documents, it says:
>
>
> "Returns the contingency table of two vectors A and B. The resulting table F consists of max(A) rows and max(B) columns."
>
>
> Suppose I've 2 matrix A and B of this form:
>
>
> A = matrix(1, 1, 10)
> B = matrix(seq(10,1, -1), 10, 1)
>
>
> I should have a matrix of form
>
> C = matrix(1, 10, 1).
>
>
> But I'm getting
>
> C  = matrix(1, 1, 10).
>
>
> Also, what is the difference between "Group form" and "Scalar form"?
>
>
> Thank you!
>
> Arijit
>