[R] How to find row maximum of two columns

[Dale Steele]

Hello -- Given the 10x2 matrix below, my goal is to create a vector
which contains the maximum of column 1 and column 2, or the only value
if there is an NA in one column.  I experimented with max.col without
success.  Thanks.  --Dale

 > > tmax.m
        tmaxhme tmaxer
   [1,]   101.0   99.8
   [2,]   102.5   99.0
   [3,]   100.6   98.4
   [4,]      NA  100.5
   [5,]   101.0   99.4
   [6,]      NA   97.6
   [7,]      NA   99.0
   [8,]    99.0   98.4
   [9,]      NA   98.5
  [10,]      NA   99.1