[R] Creating data frame from individual files

[arun]

Hi,

suppose, you have 3 files with 2 columns:
named.list<- list(structure(list(col1 = 1:6, col2 = c(0.5, 0.2, 0.3, 0.3, 
0.1, 0.2)), .Names = c("col1", "col2"), class = "data.frame", row.names = c(NA, 
-6L)), structure(list(col1 = 1:6, col2 = c(0.9, 0.7, 0.5, 0.2, 
0.5, 0.2)), .Names = c("col1", "col2"), class = "data.frame", row.names = c(NA, 
-6L)), structure(list(col1 = 7:12, col2 = c(0.1, 0.5, 0.9, 0.3, 
0.6, 0.4)), .Names = c("col1", "col2"), class = "data.frame", row.names = c(NA, 
-6L)))

 named.list1<-do.call(cbind,named.list)

 mat1<-as.matrix(named.list1[!duplicated(as.list(named.list1))])
 dimnames(mat1)<-NULL
 mat1
#     [,1] [,2] [,3] [,4] [,5]
#[1,]    1  0.5  0.9    7  0.1
#[2,]    2  0.2  0.7    8  0.5
#[3,]    3  0.3  0.5    9  0.9
#[4,]    4  0.3  0.2   10  0.3
#[5,]    5  0.1  0.5   11  0.6
#[6,]    6  0.2  0.2   12  0.4

Because you mentioned 72 files and you need 70 columns in the result matrix, I think you need only the first column.
In that case:

 named.list2<-do.call(cbind,lapply(named.list,`[`,1))
mat2<- as.matrix(named.list2[!duplicated(as.list(named.list2))])
 dimnames(mat2)<-NULL
 mat2
#     [,1] [,2]
#[1,]    1    7
#[2,]    2    8
#[3,]    3    9
#[4,]    4   10
#[5,]    5   11
#[6,]    6   12

I am not sure this is what you wanted.
A.K.

----- Original Message -----
From: Adrian Johnson <oriolebaltimore at gmail.com>
To: r-help <r-help at r-project.org>
Cc: 
Sent: Wednesday, April 3, 2013 7:05 PM
Subject: [R] Creating data frame from individual files

Dear Group:
I have 72 files (.txt).

Each file has 2 columns and column 1 is always identical for all 70 files.
Each file has 90,799 rows and is standard across all files.

I want to create a matrix 40(rows) x 70 columns.

I tried :

temp = list.files(pattern="*.txt")
named.list <- lapply(temp, read.delim)
library(data.table)
files.matrix <-rbindlist(named.list)

> dim(files.matrix)
[1] 6537456       2

What happened here is all 90K rows for 72 files were rbinded.

I want to cbind.

Could anyone please help me.
Thanks
Adrian

    [[alternative HTML version deleted]]

______________________________________________
R-help at r-project.org mailing list
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.