[R] Mann-Kendall test for many independent columns data set at a time

[Desta Yoseph]

I am analyzing trend test using Mann-kendall monotonic trendtest for 10,368 independent grid cell, each grid has 34 years dataset.  I supposed to find Kendall “tau” for each gridcell (each grid has 34 years data). The data is arranged in column wise (Iattached  part of the grid dataset  as a sample).

To find Kendall tau, I wrote R script as:


desta<-read.csv("rainfall.csv",header=T, sep=",")

require(Kendall) 

MK<-function(y) {

         nc<-ncol(y)

       MannKendalltau<-numeric(nc)

        for(i in 2:nc){

           MannKendalltau[i]<-MannKendall(y[,i])

           }

            MannKendalltau

    }

    MK(desta)


The result displayed both “tau” and “2-sided pvalue”.  But, I wantonly “tau” value that is printed in organized way. Anyone can tell me how can Iget orderly printed “tau” value  for allgrid cells at a time.    


Thank you for your help in advance,Desta WodeboTU-DresdenGermany