Edited to give a fuller example of code and specific issue
I'm writing a function to produce time series plots of stock prices. However, I'm getting the following error
Error in eval(expr, envir, enclos) : object 'df1234' not found
Here's an example of the function:
plot.prices <- function(df1234) {
require(ggplot2)
g <- ggplot(df1234, aes(x= as.Date(Date, format= "%Y-%m-%d"), y= df1234[, 3],
colour= brewer.pal(12,"Set3")[1])) + geom_point(size=1)
g + geom_point(aes(x= date, y = df1234[, 4],
colour= brewer.pal(12,"Set3")[2]), size=1)
# ... code not shown...
g
}
And example data:
spy <- read.csv(file= 'http://ichart.finance.yahoo.com/table.csv?s=SPY&d=11&e=1&f=2012&g=d&a=0&b=29&c=1993&ignore=.csv', header= T)
plot.prices(spy) # produces error
g <- ggplot(spy, aes(x= as.Date(Date, format= "%Y-%m-%d"), y= spy[, 3],
colour= brewer.pal(12,"Set3")[1])) + geom_point(size=1)
g + geom_point(aes(x= as.Date(Date), y = spy[, 4],
colour= brewer.pal(12,"Set3")[2]), size=1)
## does not produce error
As you can see, the code is identical. I get an error if the call to ggplot() is INSIDE the function but not if the call to ggplot() is OUTSIDE the function.