Hy,
I have this data frame, I want download the data from Yahoo and Calculate Percent Change (Delt function in Quantmod)
View(Equity)
Symbol
1 A
2 AA
3 AAC
I made a cycle
m<-nrow(Equity)
for (i in 1:m) {
EquityDF <- Equity[i,]
Data<-getSymbols(EquityDF,src="yahoo")
Delt[i]<-apply(EquityDF[,1:5], 2, function(x) Delt(x, k=1)*100)
}
But I received this error
Error in EquityDF[, 1:5] : incorrect number of dimensions
I know why this error appear because if I make
EquityDF
the output it is
"A"
how can I fix this ?
Thanks
This happens because EquityDF is still a character. To retrieve the corresponding data you must use get: get(EquityDF)[, 1:5]
Additionally I'd suggest to call getSymbols only once, so that you retrieve all your needed data in a single call, thus your code can be simplified to:
Equity <- data.frame(Symbol = c("A","AA","AAC"), stringsAsFactors = FALSE)
getSymbols(Equity[, 1], src="yahoo")
Delt <- lapply(mget(Equity[, 1]), function(y){
apply(y[, 1:5], 2, function(x) Delt(x, k=1)*100)})
Related
I have a dataframe with ~9000 rows of human coded data in it, two coders per item so about 4500 unique pairs. I want to break the dataset into each of these pairs, so ~4500 dataframes, run a kripp.alpha on the scores that were assigned, and then save those into a coder sheet I have made. I cannot get the loop to work to do this.
I can get it to work individually, using this:
example.m <- as.matrix(example.m)
s <- kripp.alpha(example.m)
example$alpha <- s$value
However, when trying a loop I am getting either "Error in get(v) : object 'NA' not found" when running this:
for (i in items) {
v <- i
v <- v[c("V1","V2")]
v <- assign(v, as.matrix(get(v)))
s <- kripp.alpha(v)
i$alpha <- s$value
}
Or am getting "In i$alpha <- s$value : Coercing LHS to a list" when running:
for (i in items) {
i.m <- i[c("V1","V2")]
i.m <- as.matrix(i.m)
s <- kripp.alpha(i.m)
i$alpha <- s$value
}
Here is an example set of data. Items is a list of individual dataframes.
l <- as.data.frame(matrix(c(4,3,3,3,1,1,3,3,3,3,1,1),nrow=2))
t <- as.data.frame(matrix(c(4,3,4,3,1,1,3,3,1,3,1,1),nrow=2))
items <- c("l","t")
I am sure this is a basic question, but what I want is for each file, i, to add a column with the alpha score at the end. Thanks!
Your problem is with scoping and extracting names from objects when referenced through strings. You'd need to eval() some of your object to make your current approach work.
Here's another solution
library("irr") # For kripp.alpha
# Produce the data
l <- as.data.frame(matrix(c(4,3,3,3,1,1,3,3,3,3,1,1),nrow=2))
t <- as.data.frame(matrix(c(4,3,4,3,1,1,3,3,1,3,1,1),nrow=2))
# Collect the data as a list right away
items <- list(l, t)
Now you can sapply() directly over the elements in the list.
sapply(items, function(v) {
kripp.alpha(as.matrix(v[c("V1","V2")]))$value
})
which produces
[1] 0.0 -0.5
When working with R I frequently get the error message "subscript out of bounds". For example:
# Load necessary libraries and data
library(igraph)
library(NetData)
data(kracknets, package = "NetData")
# Reduce dataset to nonzero edges
krack_full_nonzero_edges <- subset(krack_full_data_frame, (advice_tie > 0 | friendship_tie > 0 | reports_to_tie > 0))
# convert to graph data farme
krack_full <- graph.data.frame(krack_full_nonzero_edges)
# Set vertex attributes
for (i in V(krack_full)) {
for (j in names(attributes)) {
krack_full <- set.vertex.attribute(krack_full, j, index=i, attributes[i+1,j])
}
}
# Calculate reachability for each vertix
reachability <- function(g, m) {
reach_mat = matrix(nrow = vcount(g),
ncol = vcount(g))
for (i in 1:vcount(g)) {
reach_mat[i,] = 0
this_node_reach <- subcomponent(g, (i - 1), mode = m)
for (j in 1:(length(this_node_reach))) {
alter = this_node_reach[j] + 1
reach_mat[i, alter] = 1
}
}
return(reach_mat)
}
reach_full_in <- reachability(krack_full, 'in')
reach_full_in
This generates the following error Error in reach_mat[i, alter] = 1 : subscript out of bounds.
However, my question is not about this particular piece of code (even though it would be helpful to solve that too), but my question is more general:
What is the definition of a subscript-out-of-bounds error? What causes it?
Are there any generic ways of approaching this kind of error?
This is because you try to access an array out of its boundary.
I will show you how you can debug such errors.
I set options(error=recover)
I run reach_full_in <- reachability(krack_full, 'in')
I get :
reach_full_in <- reachability(krack_full, 'in')
Error in reach_mat[i, alter] = 1 : subscript out of bounds
Enter a frame number, or 0 to exit
1: reachability(krack_full, "in")
I enter 1 and I get
Called from: top level
I type ls() to see my current variables
1] "*tmp*" "alter" "g"
"i" "j" "m"
"reach_mat" "this_node_reach"
Now, I will see the dimensions of my variables :
Browse[1]> i
[1] 1
Browse[1]> j
[1] 21
Browse[1]> alter
[1] 22
Browse[1]> dim(reach_mat)
[1] 21 21
You see that alter is out of bounds. 22 > 21 . in the line :
reach_mat[i, alter] = 1
To avoid such error, personally I do this :
Try to use applyxx function. They are safer than for
I use seq_along and not 1:n (1:0)
Try to think in a vectorized solution if you can to avoid mat[i,j] index access.
EDIT vectorize the solution
For example, here I see that you don't use the fact that set.vertex.attribute is vectorized.
You can replace:
# Set vertex attributes
for (i in V(krack_full)) {
for (j in names(attributes)) {
krack_full <- set.vertex.attribute(krack_full, j, index=i, attributes[i+1,j])
}
}
by this:
## set.vertex.attribute is vectorized!
## no need to loop over vertex!
for (attr in names(attributes))
krack_full <<- set.vertex.attribute(krack_full,
attr, value = attributes[,attr])
It just means that either alter > ncol( reach_mat ) or i > nrow( reach_mat ), in other words, your indices exceed the array boundary (i is greater than the number of rows, or alter is greater than the number of columns).
Just run the above tests to see what and when is happening.
Only an addition to the above responses: A possibility in such cases is that you are calling an object, that for some reason is not available to your query. For example you may subset by row names or column names, and you will receive this error message when your requested row or column is not part of the data matrix or data frame anymore.
Solution: As a short version of the responses above: you need to find the last working row name or column name, and the next called object should be the one that could not be found.
If you run parallel codes like "foreach", then you need to convert your code to a for loop to be able to troubleshoot it.
If this helps anybody, I encountered this while using purr::map() with a function I wrote which was something like this:
find_nearby_shops <- function(base_account) {
states_table %>%
filter(state == base_account$state) %>%
left_join(target_locations, by = c('border_states' = 'state')) %>%
mutate(x_latitude = base_account$latitude,
x_longitude = base_account$longitude) %>%
mutate(dist_miles = geosphere::distHaversine(p1 = cbind(longitude, latitude),
p2 = cbind(x_longitude, x_latitude))/1609.344)
}
nearby_shop_numbers <- base_locations %>%
split(f = base_locations$id) %>%
purrr::map_df(find_nearby_shops)
I would get this error sometimes with samples, but most times I wouldn't. The root of the problem is that some of the states in the base_locations table (PR) did not exist in the states_table, so essentially I had filtered out everything, and passed an empty table on to mutate. The moral of the story is that you may have a data issue and not (just) a code problem (so you may need to clean your data.)
Thanks for agstudy and zx8754's answers above for helping with the debug.
I sometimes encounter the same issue. I can only answer your second bullet, because I am not as expert in R as I am with other languages. I have found that the standard for loop has some unexpected results. Say x = 0
for (i in 1:x) {
print(i)
}
The output is
[1] 1
[1] 0
Whereas with python, for example
for i in range(x):
print i
does nothing. The loop is not entered.
I expected that if x = 0 that in R, the loop would not be entered. However, 1:0 is a valid range of numbers. I have not yet found a good workaround besides having an if statement wrapping the for loop
This came from standford's sna free tutorial
and it states that ...
# Reachability can only be computed on one vertex at a time. To
# get graph-wide statistics, change the value of "vertex"
# manually or write a for loop. (Remember that, unlike R objects,
# igraph objects are numbered from 0.)
ok, so when ever using igraph, the first roll/column is 0 other than 1, but matrix starts at 1, thus for any calculation under igraph, you would need x-1, shown at
this_node_reach <- subcomponent(g, (i - 1), mode = m)
but for the alter calculation, there is a typo here
alter = this_node_reach[j] + 1
delete +1 and it will work alright
What did it for me was going back in the code and check for errors or uncertain changes and focus on need-to-have over nice-to-have.
I am trying to cycle through a list of symbols and download the data and save it to a csv file. individual stocks work perfectly fine if it is there, but it stops if there is an error and I do not know how to handle errors (new to R) I used part of an answer here, but I am unable to find answer on error handling while looping it to save it to file.
quantmod omitting tickers in getSymbols
startDate = Sys.Date()- 365
pth = "C:\\"
tickers <- c("LMT","AAPL","AMT", "GOOG")
#the sapply method works by not stopping when it has issues with LMT and still it goes not to dwld AAPL,
library(quantmod)
WoW <- new.env()
sapply(tickers, function(x){
try(
getSymbols(
x,
src ="google",
from =startDate,
env=WoW),
silent=TRUE)
})
#Now for the looping to save to file, somehow it does not go althe way till GOOG. it stops at AAPL
#Error in data.frame(sym) : row names contain missing values.
for (i in 1:length(tickers) ) {
col <- c( "Open","High","Low","Close","Volume")
sym <- eval(parse(text=paste("WoW$",tickers[i],sep="")))
if (!is.null(nrow(sym))){
colnames(sym) <- col
sym <- data.frame(sym)
sym <- cbind(BizDay = 0, sym)
sym$BizDay <- rownames(sym)
op <- paste0(pth,tickers[i],".csv")
print(op)
write.table(sym, file=op, na="", sep=",", row.names = FALSE)
}
}
Any pointers on how to handle basic errors? I have to run through full security list, and have to make sure that i handle those. but right now stuck on this.
Thanks
Got it to work with nrow(sym) > 1 check.
I am trying to call a Azure Machine Learning web service from Microsoft Power BI (Visualization tool) through R. The process demands input to be given as a list. So for that I am converting my input to a list in R. Below is my code.
dataset <- data.frame(sqlQuery(conn, "SELECT * FROM dbo.Automobile"))
close(conn)
if(nrow(dataset)>0)
{
dataset <- dataset[,c(-1, -14)]
dataset <- na.omit(dataset)
createList <- function(dataset)
{
temp <- apply(dataset, 1, function(x) as.vector(paste(x, sep = "")))
colnames(temp) <- NULL
temp <- apply(temp, 2, function(x) as.list(x))
return(temp)
}
...
I am very new to R so above code is from Power BI's documentation only. But is gives the following error :
dim(X) must have a positive length
I tried googling this error and applied some of the workarounds like
1. using lapply function
2. adding drop=F
but kept on returning errors.
Can anyone help me with this ?
Apologies for long post! I'm new to R and have been working hard to improve my command of the language. I stumbled across this interesting project on modelling football results: http://www1.maths.leeds.ac.uk/~voss/projects/2010-sports/JamesGardner.pdf
I keep running into problems when I run the code to Simulate a Full Season (first mentioned page 36, appendix page 59):
Games <- function(parameters)
{
teams <- rownames(parameters)
P <- parameters$teams
home <- parameters$home
n <- length(teams)
C <- data.frame()
row <- 1
for (i in 1:n) {
for (j in 1:n) {
if (i != j) {
C[row,1] <- teams[i]
C[row,2] <- teams[j]
C[row,3] <- rpois(1, exp(P[i,]$Attack - P[j,]$Defence + home))
C[row,4] <- rpois(1, exp(P[j,]$Attack - P[i,]$Defence))
row <- row + 1
}
}
}
return(C)
}
Games(TeamParameters)
The response I get is
Error in `*tmp*`[[j]] : subscript out of bounds
When I attempt a traceback(), this is what I get:
3: `[<-.data.frame`(`*tmp*`, row, 1, value = NULL) at #11
2: `[<-`(`*tmp*`, row, 1, value = NULL) at #11
1: Games(TeamParameters)
I don't really understand what the error means and I would appreciate any help. Once again, apologies for the long post but I'm really interested in this project and would love to learn what the problem is!
The data.frame objects are not extendable by row with the [<-.data.frame operation. (You would need to use rbind.) You should create an object that has sufficient space, either a pre-dimensioned matrix or data.frame. If "C" is an object of 0 rows, then trying to assign to row one will fail. There is a function named "C", so you might want to make its name something more distinct. It also seems likely that there are more efficient methods than the double loop but you haven't describe the parameter object very well.
You may notice that the Appendix of that paper you cited shows how to pre-dimension a dataframe:
teams <- sort(unique(c(games[,1], games[,2])), decreasing = FALSE)
T <- data.frame(Team=teams, ... )
... and the games-object was assumed to already have the proper number of rows and the results of computations were assigning new column values. The $<- operation will succeed if there is no current value for that referenced column.