CODEWITHSUNDEEP
rloops
Ashish Jalan
Ashish Jalan

Reputation: 181

Loop in a column-with conditions only once

data<- c(100,101,102,103,104,99,98,97,94,93,103,90,104,105,110)
date<- Sys.Date()-15:1
file<- xts(data,date)
colnames(file)<- "CLOSE"
file$high<- cummax(file$CLOSE)
file$trade <- 0
file$trade[file$high*.95>=file$CLOSE] <- 1
file$trade[file$high*.90>=file$CLOSE] <- 2
file$trade[file$high*.85>=file$CLOSE] <- 3

file
        CLOSE high trade
2013-07-06   100  100     0
2013-07-07   101  101     0
2013-07-08   102  102     0
2013-07-09   103  103     0
2013-07-10   104  104     0
2013-07-11    99  104     0
2013-07-12    98  104     1
2013-07-13    97  104     1
2013-07-14    94  104     1
2013-07-15    93  104     2
2013-07-16   103  104     0
2013-07-17    90  104     2
2013-07-18   104  104     0
2013-07-19   105  105     0
2013-07-20   110  110     0

I need to modify trade column, so after i get my first "1" then all elements would be zero until i get 2 and then all elements should be 0, till i get 3 and so on.

Upvotes: 3

Views: 99

Answers (2)

Erich Studerus
Erich Studerus

Reputation: 557

I think, you could simply do:

> file$trade[duplicated(file$trade)] <- 0

Upvotes: 2

semibruin
semibruin

Reputation: 1013

You don't need a loop to do this. Indeed, you simply need to find the positions of the first "1", "2",.... Try the following codes.

rank.trade <- rank(file$trade, ties.method = "first")
marks <- cumsum(head(table(file$trade), -1)) + 1
black.list <- is.na(match(rank.trade, marks))
file$trade[black.list] <- 0

Upvotes: 2

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