From h@wickh@m @ending from gm@il@com  Sat Jul  7 22:32:28 2018
From: h@wickh@m @ending from gm@il@com (Hadley Wickham)
Date: Sat, 7 Jul 2018 15:32:28 -0500
Subject: [Rd] Testing for vectors
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On Sat, Jul 7, 2018 at 1:50 PM, Gabe Becker <becker.gabe at gene.com> wrote:
> Hadley,
>
>>
>> I was thinking primarily of completing the set of is.matrix() and
>> is.array(), or generally, how do you say: is `x` a 1d dimensional
>> thing?
>
>
> Can you clarify what you mean by dimensionality sense and specifically 1d
> here?

What do we call a vector that is not an array? (or matrix)

What do we call an object that acts 1-dimensional? (i.e. has
length(dim()) %in% c(0, 1)) ?

> You can also have an n x 1 matrix, which technically has 2 dimensions but
> conceptually is equivalent to a 1d array and/or a vector.

Yes. You can also have array that's n x 1 x 1.

> Also, are you including lists in your conceptions of 1d vector here? I'm
> with Duncan here, in that i'm having trouble understanding exactly what you
> want to do without a bit more context.

Isn't it standard terminology that a vector is the set of atomic vectors + list?

Hadley

-- 
http://hadley.nz



[Rd] Testing for vectors
Hadley Wickham