search for: colmuns

Dear R helpers,   I have two queries.   (1) If the dataset contains some variables having all the entries = 0 and while analysing I want to delete those pericular columns, how do acheive this. i.e.   dataset1   sr_no    var1      var2       var3        var4        var5 1           5           0          3              1           0 2           3           0          2              9           0

...ector)}: length of a vector {\tt 1:3}: is the vector {\tt 1,2,3} {\tt rep(x,n)}: repeats the vector {\tt x n} times {\tt c(1,2,3)}: creates the same vector \hangpara{2em}{1}{\tt cbind(a,b,c), rbind()}: binds columns or rows into a matrix {\tt merge}: merge data frames {\tt matrix(numbers,rows,colmuns)}: creates a matrix {\tt data.frame(vector list)}: makes a data frame \hangpara{2em}{1}{\tt as.factor(), as.matrix(), as.vector()}: conversion \hangpara{2em}{1}{\tt is.factor(), is.matrix(), is.vector()}: what it is {\tt t()}: switch rows and columns {\tt which(x==a)}: returns indices of {\tt...

Hi: I have made a lot of progress reading and manipulating large data files, thanks to the help of several of you. I am now stuck with writing the final file with the following error (see also the full transcript below): Error in as.matrix.data.frame(x) : length of dimnames[2] not equal to array extent I do not know what it means and could not find how to get around that in the manual nor