matrix transpose

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This is supposed to be an easy operation, but R 2.8.1 on Mac OS X  
gives me a
lot trouble. the t() function simply does not work properly.  What  
I mean is
it works sometimes but does not work at the most of the time, even  
with the
same matrix.

this is an example taken from R help

a <- matrix(1:30, 5,6)
t(a)
Error in t(a) : unused argument(s) (1:30)

It just gives this error.  If I restart my Mac (Yeah, have to  
restart the
OS), then there are chances t() works, but sometimes it still does  
not work.

Can anyone give me another way to compute the transpose in R?
No.  That's the only way. :-)

(1) I have no problem doing your example (on Mac OS X).

(2) The error is weird in that you passed the argument ``1:30'' to  
matrix()
     not to t().  Something is corrupted in your system.  What  
happens when
     you just type ``a'' (rather than t(a)) after creating a?  What  
happens
     when you type ``t'' (no parentheses) and ``matrix'' (no  
parentheses)?

(3) Possibly you have a workspace that is corrupted in some way.  Try  
starting
     R with the --no-restore-data flag and see what happens.  Or  
move .RData
     to (say) ``save.RData'' before you start R, and see what happens.

(4) Good luck!

	cheers,

		Rolf Turner

######################################################################
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This is supposed to be an easy operation, but R 2.8.1 on Mac OS X gives me a
lot trouble. the t() function simply does not work properly.  What I mean is
it works sometimes but does not work at the most of the time, even with the
same matrix.

this is an example taken from R help

a <- matrix(1:30, 5,6)
t(a)

Error in t(a) : unused argument(s) (1:30)

It just gives this error.  If I restart my Mac (Yeah, have to restart the
OS), then there are chances t() works, but sometimes it still does not work.

does it ever fail if you try the example in a fresh r session (i.e., one
without anything executed before this code)?

when it fails, what is t?  have you redefined t to be some other
function, in particular, a no-argument one, as here:

t = function() NULL

a = matrix(1:30, 5, 6)
t(a)
# Error in t(a) : unused argument(s) (1:30)

this is most likely what happens here.

vQ
Here's one way that seems to work:

a <- matrix(1:30,5,6)
# Create a target for the transpose
b <- matrix(1:(nrow(a)*ncol(a)),ncol(a),nrow(a))
# populate b with the transpose of a
for (i in 1:ncol(a)) { b[i,1:(nrow(a))] <- a[1:(nrow(a)),i]}
# Check:  Did it work?
all.equal(b,t(a))

I'm sure there's a more "R-like" way of doing this...

Cheers,
Dan Viar
Chesapeake, VA
On 16/02/2009, at 8:36 AM, Roger wrote:

This is supposed to be an easy operation, but R 2.8.1 on Mac OS X gives me
a
lot trouble. the t() function simply does not work properly.  What I mean
is
it works sometimes but does not work at the most of the time, even with
the
same matrix.

this is an example taken from R help

a <- matrix(1:30, 5,6)
t(a)
Error in t(a) : unused argument(s) (1:30)

It just gives this error.  If I restart my Mac (Yeah, have to restart the
OS), then there are chances t() works, but sometimes it still does not
work.

Can anyone give me another way to compute the transpose in R?
No.  That's the only way. :-)

(1) I have no problem doing your example (on Mac OS X).

(2) The error is weird in that you passed the argument ``1:30'' to matrix()
   not to t().  Something is corrupted in your system.  What happens when
   you just type ``a'' (rather than t(a)) after creating a?  What happens
   when you type ``t'' (no parentheses) and ``matrix'' (no parentheses)?

(3) Possibly you have a workspace that is corrupted in some way.  Try
starting
   R with the --no-restore-data flag and see what happens.  Or move .RData
   to (say) ``save.RData'' before you start R, and see what happens.

(4) Good luck!

       cheers,

               Rolf Turner

######################################################################
Attention:\ This e-mail message is privileged and confid...{{dropped:9}}

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On 16/02/2009, at 8:36 AM, Roger wrote:

This is supposed to be an easy operation, but R 2.8.1 on Mac OS X
gives me a
lot trouble. the t() function simply does not work properly.  What I
mean is
it works sometimes but does not work at the most of the time, even
with the
same matrix.

this is an example taken from R help

a <- matrix(1:30, 5,6)
t(a)
Error in t(a) : unused argument(s) (1:30)

It just gives this error.  If I restart my Mac (Yeah, have to restart
the
OS), then there are chances t() works, but sometimes it still does
not work.

Can anyone give me another way to compute the transpose in R?
No.  That's the only way. :-)

nonsense.  the other way is:

base::t(a)

if this works while t(a) fails, the problem is solved (= do *not*
redefine t).  if this doesn't work, complain again ;)

vQ