Message-ID: <1373051800.36586.YahooMailNeo@web142601.mail.bf1.yahoo.com>
Date: 2013-07-05T19:16:40Z
From: arun
Subject: Filter Dataframe for Alarm for particular column(s).
Hi,
May be this helps:
If you had showed your solution, it would be easier to compare.
res<-data.frame(lapply(sapply(MyDF[,c(2,4)],function(x) {x1<-which(c(0,diff(x))<0);x1[length(x1)==0]<-0;x1}),`[`,1))
?res
#? TNH BIX
#1?? 3?? 9
#Speed
?set.seed(24)
?MyDFNew<- data.frame(TNH=sample(0:1,1e6,replace=TRUE),BIX=sample(0:1,1e6,replace=TRUE))
system.time(res1<-data.frame(lapply(sapply(MyDFNew,function(x) {x1<-which(c(0,diff(x))<0);x1[length(x1)==0]<-0;x1}),`[`,1)))
#?? user? system elapsed
#? 0.364?? 0.000?? 0.363
?res1
#? TNH BIX
#1?? 7?? 2
?MyDFNew[1:10,]
#?? TNH BIX
#1??? 0?? 1
#2??? 0?? 0
#3??? 1?? 1
#4??? 1?? 1
#5??? 1?? 0
#6??? 1?? 0
#7??? 0?? 1
#8??? 1?? 1
#9??? 1?? 1
#10?? 0?? 0
A.K.
Hi,
Hi here i have a dataframe called MyDF.
a<-c(1,1,1,1,1,0,0,0,1,1)
b<-c(1,1,0,1,1,0,0,0,1,1)
c<-c(1,1,1,1,1,1,1,0,1,1)
d<-c(1,1,1,1,1,1,1,1,0,1)
MyDF<-data.frame(DWATT=a,TNH=b,CSGV=c,BIX=d)
My requirement is, here i need a function - to get for a
particular row number(s), when particular column(s) value change from
one-to-zero ?(for the first change). Suppose there is no change is
happening then it should return "Zero"
For example, ?Using MyDF,
DWATT TNH CSGV BIX
1 ? 1 ? ?1 ? 1
1 ? 1 ? ?1 ? 1
1 ? 0 ? ?1 ? 1
1 ? 1 ? ?1 ? 1
1 ? 1 ? ?1 ? 1
0 ? 0 ? ?1 ? 1
0 ? 0 ? ?1 ? 1
0 ? 0 ? ?0 ? 1
1 ? 1 ? ?1 ? 0
1 ? 1 ? ?1 ? 1
Here i want to know, the row number where TNH-column and BIX-column values change happening from one-to-zero for the first time.
Note:- Suppose there is no change is happening then it should return "Zero"
Answer should be ?a dataframe with single row.
So here answer should return a dataframe like this.
TNH ?BIX
---- ? ?------
3 ? ? ?9
i used some ways to get a solution using loops. But there is a bulk files with bulk rows to process.
So performace is most important. Could someone please suggest better ideas ?
Thanks,
Antony.