Message-ID: <1cc651638ac339f933b7bd23163c48c2@openmailbox.org>
Date: 2017-02-20T21:10:20Z
From: message
Subject: use table function with data frame subsets
Readers,
Data set:
20170101,10020,A,b,Y
20170101,10020,B,b,N
20170101,10020,C,d,Y
20170102,20001,C,d,Y
20170102,20001,D,m,Y
20170102,20001,L,a,Y
testtable<-read.csv('~/tmp/data.csv',header=F)
testtablea<-testtable[grep('^10',testtable[,2]),]
> testtable
V1 V2 V3 V4 V5
1 20170101 10020 A b Y
2 20170101 10020 B b N
3 20170101 10020 C d Y
4 20170102 20001 C d Y
5 20170102 20001 D m Y
6 20170102 20001 L a Y
> testtablea
V1 V2 V3 V4 V5
1 20170101 10020 A b Y
2 20170101 10020 B b N
3 20170101 10020 C d Y
> table(testtable[,4],testtable[,5])
N Y
a 0 1
b 1 1
d 0 2
m 0 1
> table(testtablea[,4],testtablea[,5])
N Y
a 0 0
b 1 1
d 0 1
m 0 0
Wy do values for rows beginning 'a' and 'm' appear when they do not
satisfy the regular expression for the object 'testtablea'?
Please, how to use the 'table' function to show:
> table(testtablea[,4],testtablea[,5])
N Y
b 1 1
d 0 1
Thanks.