How to force a vector to be column or row vector?

From: Gabor Grothendieck
Try this:

rbind(c(x))
cbind(c(x))
t(c(x))
The c() is not needed above.

Also, this might be a better way of computing a quadratic form:
x <- 1:3
m <- matrix(sample(1:9), 3, 3)
crossprod(crossprod(m, x), x) 
[,1]
[1,]  202
t(x) %*% m %*% x   # Just checking...
[,1]
[1,]  202

In R, it usually makes little difference whether a vector is row-vector or
column-vector.

Andy
On 2/2/06, Michael <comtech.usa at gmail.com> wrote:
Hi all,

I tended to use rbind, or cbind to force a vector be be 
deemed as a column
or row vector. This is very important if I want to do 
things like u' * A *
u, where u' is a row vector and u is a column vector, 
regardless of what
originall format  the "u" is... I want to recast it to 
column vector or row
vector...  How can I do that?

----------------------------------------------------

b_hat=solve(t(X) %*% X) %*% t(X) %*% Y;

attr(b_hat, "dim")
[1] 4 1

rbind(b_hat)
      [,1]
 -4.814763
V -5.804245
 -5.122668
 -4.308326

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From: Gabor Grothendieck
Try this:

rbind(c(x))
cbind(c(x))
t(c(x))
The c() is not needed above.
The poster asked for an expression that would work "regardless of
the original form" of the vector -- row, column or neither.  The c
gets it into a known form first.  For example:
cbind(matrix(1,1,3))  # not a column vector!
[,1] [,2] [,3]
[1,]    1    1    1