how to add median value to rows? [closed]

问题:

I have a data frame (data) with 53 columns (ID column plus 52 numeric values). I can add a column with mean with the following:

data$mean <- rowMeans(data[,2:51],na.rm = TRUE) # add mean of rows

But, I cannot do the same for median with the following:

data$medians <- rowMedians(month.sum[,2:51],na.rm = TRUE) # add medians of rows

I installed the package matrixStats which includes rowMedians, but it does not work for me.

回答1:

You can apply arbitrary functions to rows with apply. Use

apply(data[,2:51],1, median, na.rm = TRUE)

Read the ?apply help page for more information.