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Base function for flipping matrices

4 messages · Hadley Wickham, Hans W Borchers, Bert Gunter +1 more

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Hi all,

Are there base functions that do the equivalent of this?

fliptb <- function(x) x[nrow(x):1, ]
fliplr <- function(x) x[, nrow(x):1]

Obviously not hard to implement (although it needs some more checks),
just wondering if it had already been implemented.

Hadley
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Hadley Wickham <hadley <at> rice.edu> writes:
See functions flipud(), fliplr() in package 'matlab' (or 'pracma').
Those are the names of corresponding functions in MATLAB.

Hans Werner
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Hadley:

Dunno.

But if not,  it seems to me that it should be added as an array method
to ?rev with an argument specifying which indices to rev() over.

Cheers,
Bert
On Sat, Dec 31, 2011 at 7:08 AM, Hadley Wickham <hadley at rice.edu> wrote:

  
    
#
Hadley,
 Presumably for fliplr you meant ncol(x)

fliplr <- function(x) x[, ncol(x):1]

Bill
On Dec 31, 2011, at 9:08 AM, Hadley Wickham wrote:

            
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