I have a program where the following code works fine: df.opt$Delta <- apply(df.opt, 1, function(x) EuropeanOption(x["CallPutString"], x["UnderlyingPrice"], x["StrikePrice"], 0, interest.rate, x["FractionalExpiration"], x["Vol"])[[2]])
However, the code below fails: #df.opt$Delta <- apply(df.opt, 1, function(x) EuropeanOption(x$CallPutString, #x["UnderlyingPrice"], x["StrikePrice"], 0, interest.rate, x["FractionalExpiration"], #x["Vol"])[[2]]) Here df.opt is a data frame and European Option is a function in the package RQuantLib. The only difference between the two pieces of code is that a column of the data frame is accessed using "$" in the first case and brackets in the second case. Sorry if this is a trivial question, but could somebody tell me the reason for this behavior? FS ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
