contingency table

This is my list.
obs1    obs2    exp1     exp2

3           8          725      875
0           0           58        70
3           7          435      525
10         7          754      910
0           1          145     175

and i want result in contingency table as

obs       3                8
exp    725          875

next table will be

obs    0         0
exp   58       70

and so on... 

Hi,

It's not clear what you intend to do with the data after restructuring, but creating a list of the 2x2 tables from each row seems a reasonable first step.

Thus, if your data above is contained in a data frame 'DF':

DF

obs1 obs2 exp1 exp2
1    3    8  725  875
2    0    0   58   70
3    3    7  435  525
4   10    7  754  910
5    0    1  145  175


# Iterate over each row in DF, returning a 2x2 matrix from each

lapply(seq(nrow(DF)), function(i) matrix(DF[i, ], 2, 2, byrow = TRUE))

[[1]]
     [,1] [,2]
[1,] 3    8   
[2,] 725  875 

[[2]]
     [,1] [,2]
[1,] 0    0   
[2,] 58   70  

[[3]]
     [,1] [,2]
[1,] 3    7   
[2,] 435  525 

[[4]]
     [,1] [,2]
[1,] 10   7   
[2,] 754  910 

[[5]]
     [,1] [,2]
[1,] 0    1   
[2,] 145  175 


This gives you a list of 5 2x2 matrices, one from each row in DF. See ?lapply, ?seq and ?matrix.

HTH,

Marc Schwartz