df = data.frame(a = c(1, 3, NA, NA),
b = c(12, 98, NA, 20),
c = c(2, 4, NA, 9),
d = c(13, 77, NA, 20),
row.names = c('o', 'p', 's', 't'))
print(df)
df = df[rowSums(is.na(df[ , 0:ncol(df)])) < ncol(df), ]
print(df)
# run:
#
# a b c d
# o 1 12 2 13
# p 3 98 4 77
# s NA NA NA NA
# t NA 20 9 20
# a b c d
# o 1 12 2 13
# p 3 98 4 77
# t NA 20 9 20
#