使用AWK求最大值

jason680

回复 9# elu_ligao

M for Maximum value

# It's OK for Normal data with positive number ( > 0 )
$ echo -e "-5\n-3\n7\n12\n3" | awk 'M<$1{M=$1}END{print M}'
12

# got the issue when all data were negative number ( < 0 )
# Note: The M will be 0, zero number, when we use it in number, M < $1,
# and the M didn't be assign and be empty
$ echo -e "-3\n-5\n-7\n-12\n-3" | awk 'M<$1{M=$1}END{print M}'


# check M variable to assign to the first number
$ echo -e "-5\n-3\n-7\n-12\n-3" | awk 'M==""||M<$1{M=$1}END{print M}'
-3