How to merge /match two files based on same column in R

Question

I have two file:

first file is single column file with header (file1$sample), contain 200 samples/line.
second is multi column and multiple rows:
```
dim(file2) 
#[1] 652 20206  
```

I want to match file1$sample and file2$sample and extract matrix (200*20206).

I tried following command:

new <- merge(file1, file2, by.x='sample', by.y='sample')

but is gives only single line file

dim(new) 
#[1] 0 20206

So please help me how can I extract (200*20206) matrix.

Thanks

Thanks nicola, I tried this , it return matrix ( 200 *20206), but all values are "NA" — mona, May 12 '16 at 10:56
Welcome to Stack Overflow! Please read the info about [how to ask a good question](http://stackoverflow.com/help/how-to-ask) and how to give a [reproducible example](http://stackoverflow.com/questions/5963269). This will make it much easier for others to help you. — zx8754, May 12 '16 at 10:56
[How to join (merge) data frames (inner, outer, left, right)?](http://stackoverflow.com/questions/1299871) — zx8754, May 12 '16 at 10:56

score 1 · Answer 1 · edited May 12 '16 at 11:51

1

Try this:

result=merge(x=file1,y=file2,by="sample",all=T)

edited May 12 '16 at 11:51

Sotos

answered May 12 '16 at 11:13

Manas Kumar

Ani Menon · Accepted Answer · 2016-05-12T14:18:36.667

0

Try this :

file1 = read.table("mydata1.txt", header=TRUE)
file2 = read.table("mydata2.txt", header=TRUE)
m=merge(file1,file2,by="sample")

edited May 12 '16 at 14:18

answered May 12 '16 at 10:52

Ani Menon

I tried: file1 = read.table("mydata1.txt", header=T) [1] 200 1, file2 = read.table("mydata2.txt", header=T) [1] 652 20206 but output is [1] 0 20206 – mona May 12 '16 at 11:08
That code should work. Post an extract of both the files & I shall post the output. – Ani Menon May 12 '16 at 14:18

2 Answers2