Re: [R] how to find and use specific column after spliting dataframe

2007-11-28 Thread Hsin-Ya Lee
Dear Dallazuanna: Thanks for your reply. It really has solved my problems. However, I have another question. How can I do, if I need to calculate such equation in all sub-dataframe? I try to use "A.split[]" to catch all sub-dataframe, but it seems can not catch the columns of all sub-dataf

Re: [R] how to find and use specific column after spliting dataframe

2007-11-28 Thread Henrique Dallazuanna
Try this: A.split[[1]]["time"] A.split[[1]][["concentration"]] test <- NULL for(i in 2:4){ test[i] <- (A.split[[1]][["time"]][i] - A.split[[1]][["time"]][i-1]) * (A.split[[1]][["concentration"]][i] - A.split[[1]][["concentration"]][i-1]) * 0.5 } On 28/11/2007, leeznar <[EMAIL PROTECTED]>

[R] how to find and use specific column after spliting dataframe

2007-11-28 Thread leeznar
Dear all: I am a new R-user and I have 2 questions about it. 1) I need to find specific sub-dataframe, and then use specific column to calculate. For example, after splitting dataframe, I find specific the sub-dataframe, such as “A.split [1]”. But, I don’t know how to find “time” and “co