dataset
And I want to pick the row which the Date is 17/12/2006 and 18/12/2006, the type of Date is character, I use the code:
a<-c('17/12/2006','18/12/2006')
NewTable<-WholeTable[which($Date %in% a)]
The error is "Error in which$Date : object of type 'closure' is not subsettable"
Then I try another code:
WholeTable$Date <- as.character(WholeTable$Date)
NewTable<-subset(WholeTable, Date == "17/12/2006"|Date == "18/12/2006")
It can create a new subset but with 0 rows.
Really confused
May be easier if you provide a minimum dataset, if I understand correctly though, this should work:
# In this example date is a factor variable with 4 levels
Wholetable <- data.frame(date = c("16/12/2006", "17/12/2006", "18/12/2006", "19/12/2006"), a = c(1:4))
Newtable <- subset(Wholetable, date == "17/12/2006" | date == "18/12/2006")
Related
I am trying my best at a simple event study in R, with some data retrieved from the Wharton Research Data Service (WRDS). I am not completely new to R, but I would describe my expertise level as intermediate. So, here is the problem. I am using the eventstudies package and one of the steps is converting the physical dates to event time frame dates with the phys2eventtime(..) function. This function takes multiple arguments:
z : time series data for which event frame is to be generated. In the form of an xts object.
Events : it is a data frame with two columns: unit and when. unit has column name of which response is to measured on the event date, while when has the event date.
Width : width corresponds to the number of days on each side of the event date. For a given width, if there is any NA in the event window then the last observation is carried forward.
The authors of the package have provided an example for the xts object (StockPriceReturns) and for Events (SplitDates). This looks like the following:
> data(StockPriceReturns)
> data(SplitDates)
> head(SplitDates)
unit when
5 BHEL 2011-10-03
6 Bharti.Airtel 2009-07-24
8 Cipla 2004-05-11
9 Coal.India 2010-02-16
10 Dr.Reddy 2001-10-10
11 HDFC.Bank 2011-07-14
> head(StockPriceReturns)
Mahindra.&.Mahindra
2000-04-03 -8.3381609
2000-04-04 0.5923550
2000-04-05 6.8097616
2000-04-06 -0.9448889
2000-04-07 7.6843828
2000-04-10 4.1220462
2000-04-11 -1.9078480
2000-04-12 -8.3286900
2000-04-13 -3.8876847
2000-04-17 -8.2886060
So I have constructed my data in the same way, an xts object (DS_xts) and a data.frame (cDS) with the columns "unit" and "when". This is how it looks:
> head(DS_xts)
61241
2011-01-03 0.024247
2011-01-04 0.039307
2011-01-05 0.010589
2011-01-06 -0.022172
2011-01-07 0.018057
2011-01-10 0.041488
> head(cDS)
unit when
1 11754 2012-01-05
2 10104 2012-01-24
3 61241 2012-01-31
4 13928 2012-02-07
5 14656 2012-02-08
6 60097 2012-02-14
These are similar in my opinion, but how it looks does not tell the whole story. I am quite certain that my problem is in how I have constructed these two objects. Below is my R code:
#install.packages("eventstudies")
library("eventstudies")
DS = read.csv("ReturnData.csv")
cDS = read.csv("EventData.csv")
#Calculate Abnormal Returns
DS$AR = DS$RET - DS$VWRETD
#Clean up and let only necessary columns remain
DS = DS[, c("PERMNO", "DATE", "AR")]
cDS = cDS[, c("PERMNO", "DATE")]
#Generate correct date format according to R's as.Date
for (i in 1:nrow(DS)) {
DS$DATE[i] = format(as.Date(toString(DS$DATE[i]), format = "%Y %m %d"), format = "%Y-%m-%d")
}
for (i in 1:nrow(cDS)) {
cDS$DATE[i] = format(as.Date(toString(cDS$DATE[i]), format = "%Y %m %d"), format = "%Y-%m-%d")
}
#Rename cDS columns according to phys2eventtime format
colnames(cDS)[1] = "unit"
colnames(cDS)[2] = "when"
#Create list of unique PERMNO's
PERMNO <- unique(DS$PERMNO)
for (i in 1:length(PERMNO)) {
#Subset based on PERMNO
DStmp <- DS[DS$PERMNO == PERMNO[i], ]
#Remove PERMNO column and rename AR to PERMNO
DStmp <- DStmp[, c("DATE", "AR")]
colnames(DStmp)[2] = as.character(PERMNO[i])
dates <- as.Date(DStmp$DATE)
DStmp <- DStmp[, -c(1)]
#Create a temporary XTS object
DStmp_xts <- xts(DStmp, order.by = dates)
#If first iteration, just create new variable, otherwise merge
if (i == 1) {
DS_xts <- DStmp_xts
} else {
DS_xts <- merge(DS_xts, DStmp_xts, all = TRUE)
}
}
#Renaming columns for matching
colnames(DS_xts) <- c(PERMNO)
#Making sure classes are the same
cDS$unit <- as.character(cDS$unit)
eventList <- phys2eventtime(z = DS_xts, events = cDS, width = 10)
So, if I run phys2eventtime(..) it returns:
> eventList <- phys2eventtime(z = DS_xts, events = cDS, width = 10)
Error in if ((location <= 1) | (location >= length(x))) { :
missing value where TRUE/FALSE needed
In addition: Warning message:
In findInterval(when, index(x)) : NAs introduced by coercion
I have looked at the original function (it is available at their GitHub, can't use more than two links yet) to figure out this error, but I ran out of ideas how to debug it. I hope someone can help me sort it out. As a final note, I have also looked at another (magnificent) answer related to this R package (question: "format a zoo object with “dimnames”=List of 2"), but it wasn't enough to help me solve it (or I couldn't yet comprehend it).
Here is the link for the two CSV files if you would like to reproduce my error (or solve it!).
i've gone through several answers and tried the following but each either yields an error or an un-wanted result:
here's the data:
Network Campaign
Moburst_Chartboost Test Campaign
Moburst_Chartboost Test Campaign
Moburst_Appnext unknown
Moburst_Appnext 1065
i'd like to replace "Test Campaign" with "1055" whenever "Network" == "Moburst_Chartboost". i realize this should be very simple but trying out these:
dataset = read.csv('C:/Users/User/Downloads/example.csv')
for( i in 1:nrow(dataset)){
if(dataset$Network == 'Moburst_Chartboost') dataset$Campaign <- '1055'
}
this yields an error: Warning messages:
1: In if (dataset$Network == "Moburst_Chartboost") dataset$Campaign <- "1055" :
the condition has length > 1 and only the first element will be used
2: In if (dataset$Network == "Moburst_Chartboost") dataset$Campaign <- "1055" :
the condition has length > 1 and only the first element will be used
etc.
then i tried:
within(dataset, {
dataset$Campaign <- ifelse(dataset$Network == 'Moburst_Chartboost', '1055', dataset$Campaign)
})
this turned ALL 4 values in row "Campaign" into "1055" over running what was there even when condition isn't met
also this:
dataset$Campaign[which(dataset$Network == 'Moburst_Chartboost')] <- 1055
yields this error, and replaced the values in the two first rows of "Campaign" with NA:
Warning message:
In `[<-.factor`(`*tmp*`, which(dataset$Network == "Moburst_Chartboost"), :
invalid factor level, NA generated
scratching my head here. new to R but this shouldn't be so hard :(
In your first attempt, you're trying to iterate over all the columns, when you only want to change the 2nd column.
In your second, you're trying to assign the value "1055" to all of the 2nd column.
The way to think about it is as an if else, where if the condition in col 1 is met, col 2 is changed, otherwise it remains the same.
dataset <- data.frame(Network = c("Moburst_Chartboost", "Moburst_Chartboost",
"Moburst_Appnext", "Moburst_Appnext"),
Campaign = c("Test Campaign", "Test Campaign",
"unknown", "1065"))
dataset$Campaign <- ifelse(dataset$Network == "Moburst_Chartboost",
"1055",
dataset$Campaign)
head(dataset)
Network Campaign
1 Moburst_Chartboost 1055
2 Moburst_Chartboost 1055
3 Moburst_Appnext unknown
4 Moburst_Appnext 1065
You may also try dataset$Campaign[dataset$Campaign=="Test Campaign"]<-1055 to avoid the use of loops and ifelse statements.
Where dataset
dataset <- data.frame(Network = c("Moburst_Chartboost", "Moburst_Chartboost",
"Moburst_Appnext", "Moburst_Appnext"),
Campaign = c("Test Campaign", "Test Campaign",
"unknown", 1065))
Try the following
dataset = read.csv('C:/Users/User/Downloads/example.csv', stringsAsFactors = F)
for( i in 1:nrow(dataset)){
if(dataset$Network[i] == 'Moburst_Chartboost') dataset$Campaign[i] <- '1055'
}
It seems your forgot the index variable. Without [i] you work on the whole vector of the data frame, resulting in the error/warning you mentioned.
Note that I added stringsAsFactors = F to the read.csv() function to make sure the strings are indeed interpreted as strings and not factors. Using factors this would result in an error like this
In `[<-.factor`(`*tmp*`, i, value = c(NA, 2L, 3L, 1L)) :
invalid factor level, NA generated
Alternatively you can do the following without using a for loop:
idx <- which(dataset$Network == 'Moburst_Chartboost')
dataset$Campaign[idx] <- '1055'
Here, idx is a vector containing the positions where Network has the value 'Moburst_Chartboost'
thank you for the help! not elegant, but since this lingered with me when going to sleep last night i decided to try to bludgeon this with some ugly code but it worked too - just as a workaround...separated to two data frames, replaced all values and then binded back...
# subsetting only chartboost
chartboost <- subset(dataset, dataset$Network=='Moburst_Chartboost')
# replace all values in Campaign
chartboost$Campaign <-sub("^.*", "1055",chartboost$Campaign)
#subsetting only "not chartboost"
notChartboost <-subset(dataset, dataset$Network!='Moburst_Chartboost')
# binding back to single dataframe
newSet <- rbind(chartboost, notChartboost)
Ugly as a duckling but worked :)
Instead of showing more2 or less2 in the column, it only shows up as NA. Why aren't the character names appearing instead?
careermore2 <- vector(mode="character",length=length(mlb$careeryrs))
"less2" <- careermore2[mlb$careeryrs<=2]
"more2" <- careermore2[mlb$careeryrs>=2]
No.seasons <- factor(careermore2,levels=c("more2","less2"),exclude=NA,ordered=TRUE)
mlb2 <- cbind(mlb,No.seasons)
str(mlb2$No.seasons)
head(mlb2$No.seasons)
mlb2[mlb2$No.seasons=="more2",]
Looking at careermore2 I would say you've got these the wrong way round:
"less2" <- careermore2[mlb$careeryrs<=2]
"more2" <- careermore2[mlb$careeryrs>=2]
That creates two objects. You really meant:
careermore2[mlb$careeryrs<=2] = "less2"
careermore2[mlb$careeryrs>=2] = "more2"
ie set the corresponding values in careermore2. And you probably want <2 or >2 rather than have = in both...
I'm new with R and working with the ALL dataset in R, and trying to create an indicator variable that defines =1 for all T-cell patients and =2 for all B-cell patients. Here is my code:
library(ALL)
data(ALL)
tcell<-c("T","T1","T2","T3","T4")
bcell<-c("B","B1","B2","B3","B4")
ALL.fac <- factor(ALL$BT, levels=1:2, labels=c(tcell,bcell))
ALL.fac
I'm getting an error which states:
Error in factor(ALL$BT, levels = 1:2, labels = c(tcell, bcell)) :
invalid 'labels'; length 10 should be 1 or 2
I'm not sure how to define the variable properly to get all the T-cells to print out as 1 and all B-cells to print as 2.
Suggestions? Thanks!
We can remove the numeric part from the 'BT' using sub and then change the levels
All.fac <- factor(sub('\\d+', '', ALL$BT) ,
levels=c('T', 'B'), labels=c(1,2))
While splitting a dataset I end up with the following error, and look for some advice to overcome it:
dt=read.csv("C:/xx/fData.csv")
testdata = dt[year(dt$date) < 2010,]
valid = dt[year(dt$date) > 2010,]
> training = dt[year(dt$date) < 2010,]
Error in as.POSIXlt.character(as.character(x), ...) :
character string is not in a standard unambiguous format
> testing = dt[year(dt$date) > 2010,]
Error in as.POSIXlt.character(as.character(x), ...) :
ps: fData looks like
| date | number
----------------------
1 |1/1/2011| 0
2 |1/2/2011| 0
Given that the first part of your string is the month day and the second part is the month you should convert your string into a date format before calling the year function
dt$date <- as.Date(dt$date,'%d/%m/%Y')