Creating Sub-Matrix

How do I get sub-matrix? Example, I would like to get matrix of size 3x7
from the matrix of size 4x7. Meaning that I try to exclude one row of the
original matrix.

Just exclude the row by negative indexing - e.g. foo[-2,]

You may want to consider reading the "Introduction to R" where all these
concepts are explained to new users.

cu
	Philipp

Dr. Philipp Pagel
Lehrstuhl f?r Genomorientierte Bioinformatik
Technische Universit?t M?nchen
Wissenschaftszentrum Weihenstephan
85350 Freising, Germany
http://mips.gsf.de/staff/pagel

Several ways, two are shown:
 > matrix(1:(4*7), 4,7)
      [,1] [,2] [,3] [,4] [,5] [,6] [,7]
[1,]    1    5    9   13   17   21   25
[2,]    2    6   10   14   18   22   26
[3,]    3    7   11   15   19   23   27
[4,]    4    8   12   16   20   24   28
 > mtx <- matrix(1:(4*7), 4,7)

 > mtx[-1,]
      [,1] [,2] [,3] [,4] [,5] [,6] [,7]
[1,]    2    6   10   14   18   22   26
[2,]    3    7   11   15   19   23   27
[3,]    4    8   12   16   20   24   28
 > mtx[2:4, ]
      [,1] [,2] [,3] [,4] [,5] [,6] [,7]
[1,]    2    6   10   14   18   22   26
[2,]    3    7   11   15   19   23   27
[3,]    4    8   12   16   20   24   28

Search terms:
--- at the R prompt
?Extract
?"["      #gets to the same page

--- in other sites:
indexing

--  
David Winsemius

Hello,

How do I get sub-matrix? Example, I would like to get matrix of size  
3x7
from the matrix of size 4x7. Meaning that I try to exclude one row  
of the
original matrix.

Thanks
-rofizah-

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