[R] counting missing values

[vincent.stoliaroff@socgen.com]

Hello R lovers
I have written a little cute function to count the number of missing value
per row in a matrix and return the percentage of missing value

it takes a lot of time to run with a 1000 rows matrix

I'd like to know if there is a function already implemented to count the
number of occurence of a given values in a vector


For information,
here is the function
count<-0
for (i in 1:nrow(Matrix))
      {
      for (j in 1:ncol(Matrix)) {if (is.na(Matrix[i,j])) count<-count+1}
      Result[i,1]<-((count/(ncol(Matrix)))*100);
      count<-0
      }
Result

thanks for any help
Vincent




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