I would like to preface this by saying that I am new to R, so I would ask that you be patient and thorough, so that I'm not completely clueless. I am trying to convert a list to numeric so that I can perform computations on it (specifically mean-center the variable), but I am running into problems. I have imported the data set into "task" (data frame). The data frame is made of factors with variable names in the first row. I am running a loop to set a variable equal to a column in the data frame. Here is an example of my problem:
for (i in 1:dim(task)[2]){ predictor.loop <- c(task[i]) predictor.loop.mc <- predictor.loop - mean(predictor.loop, na.rm=T) } I get the following error: Error in predictor.loop - mean(predictor.loop, na.rm = T) : non-numeric argument to binary operator In addition: Warning message: In mean.default(predictor.loop, na.rm = T) : argument is not numeric or logical: returning NA The column is entirely made up of numerical data, except for the header, which is a string. My problem is that I receive an error because the predictor.loop variable is not numerical, so I need to find a way to convert it. I tried using: predictor.loop <- c(as.numeric(task[i])) But I get the following error: "Error: (list) object cannot be coerced to type 'double'" If I call the variable, I can assign it to a numerical list (e.g., predictor loop <- task$variablename), but since I am assigning the variable in a loop, I have to find another way as the variable name would have to change in each loop iteration. Any help would be greatly appreciated. Thanks! -- View this message in context: http://old.nabble.com/convert-list-to-numeric-tp26155039p26155039.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.