Mean for every columm of a matrix in R : How,can I get the mean of each column, each column contain multiple value, and there are 1000 of column. I dont want to use loop for efficiency reason.
  

    For example data look like 
            
        col1                     col2         .........coln
     v1 c(10,11,12....)     c(12,11,9....)              c(12,11,9....)
     v2 c(1,1,1,1,1,1...)   c(1,1,1,1,1,1...)           c(1,1,1,1,1,1...)
     v3 c(0 ,0,1,2,3,..)    c(0 ,0,2,2,2,3,..)          c(0 ,0,2,2,2,3,..)
     v4 c(date1,dat2,....)  c(date1,dat2,....)          c(date1,dat2,....)
            

I want to calculate the mean for V1 row for every column.
 
Thanks 