Thanks David! It worked! On 17 May 2017 at 23:39, David Winsemius <dwinsem...@comcast.net> wrote: > >> On May 17, 2017, at 1:01 PM, Davide Piffer <pifferdav...@gmail.com> wrote: >> >> Thanks! This gets closer to the solution but a small problem remains. >> I get 2 rows and only one column, whereas I need a 2x2 matrix (like a >> contingency table for Fisher's exact test).Also another issue is it >> repeats the first number of the column, instead of using all 4. >> For example, first vector of df is=c(564,3825,125, 377 >> >> I get: >> >> [,1] >> [1,] 564.3112 >> [2,] 564.3112 >> >> >> But I should get >> >> [,1] [.2] >> [1,]564 125 >> [2,] 3825 377 > > ( y <- data.frame(matrix(1:40, 4, 10)) ) > ( y.mat <- lapply(y, matrix, nrow=2)) > >> head(y.mat, 3) > $X1 > [,1] [,2] > [1,] 1 3 > [2,] 2 4 > > $X2 > [,1] [,2] > [1,] 5 7 > [2,] 6 8 > > $X3 > [,1] [,2] > [1,] 9 11 > [2,] 10 12 > >> >> On 17 May 2017 at 22:35, David L Carlson <dcarl...@tamu.edu> wrote: >>> Not really enough info here since you don't specify much about the data >>> frame or how the results should be provided, but maybe something like this: >>> >>> y <- data.frame(matrix(1:100, 10, 10)) >>> y.mat <- lapply(y, matrix, nrow=2) >>> str(y.mat) >>> List of 10 >>> $ X1 : int [1:2, 1:5] 1 2 3 4 5 6 7 8 9 10 >>> $ X2 : int [1:2, 1:5] 11 12 13 14 15 16 17 18 19 20 >>> $ X3 : int [1:2, 1:5] 21 22 23 24 25 26 27 28 29 30 >>> $ X4 : int [1:2, 1:5] 31 32 33 34 35 36 37 38 39 40 >>> $ X5 : int [1:2, 1:5] 41 42 43 44 45 46 47 48 49 50 >>> $ X6 : int [1:2, 1:5] 51 52 53 54 55 56 57 58 59 60 >>> $ X7 : int [1:2, 1:5] 61 62 63 64 65 66 67 68 69 70 >>> $ X8 : int [1:2, 1:5] 71 72 73 74 75 76 77 78 79 80 >>> $ X9 : int [1:2, 1:5] 81 82 83 84 85 86 87 88 89 90 >>> $ X10: int [1:2, 1:5] 91 92 93 94 95 96 97 98 99 100 >>> >>> >>> ------------------------------------- >>> David L Carlson >>> Department of Anthropology >>> Texas A&M University >>> College Station, TX 77840-4352 >>> >>> >>> -----Original Message----- >>> From: R-help [mailto:r-help-boun...@r-project.org] On Behalf Of Davide >>> Piffer >>> Sent: Wednesday, May 17, 2017 2:18 PM >>> To: r-help@r-project.org >>> Subject: [R] converting each column of a data frame into a matrix with n >>> rows >>> >>> I need to convert each vector of a dataframe into a matrix with 2 rows >>> and 2 columns (i.e. contingency table). >>> Note I don't want to convert the entire df into a matrix! I want to >>> apply a function that converts each 4 elements vector of a df into a 2 >>> x 2 matrix. >>> >>> I wrote something like this, but it will not work: >>> >>> f_matrix=function(x){ matrix (x) >>> nrow=2} >>> matrix_y=apply(y,2,function(x) f_matrix (x)) >>> >>> ______________________________________________ >>> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >>> https://stat.ethz.ch/mailman/listinfo/r-help >>> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html >>> and provide commented, minimal, self-contained, reproducible code. >> >> ______________________________________________ >> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >> https://stat.ethz.ch/mailman/listinfo/r-help >> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html >> and provide commented, minimal, self-contained, reproducible code. > > David Winsemius > Alameda, CA, USA >
______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
