Extract Maximum and minimum value using awk

Question

How to find maximum and minimum value from the below table using awk command.

20 90 60 30
55 75 80 85
10 15 99 95
55 95 70 20
9  35 85 75

I want the output like max value=99 and min=9

Answer 1

awk '
NR == 1 { min=max=$1 }
{
    for (i=1;i<=NF;i++) {
        min = (min < $i ? min : $i)
        max = (max > $i ? max : $i)
    }
}
END {
    printf "min value = %s\n", (min == "" ? "NaN" : min)
    printf "max value = %s\n", (max == "" ? "NaN" : max)
}
' file

The test resulting in "NaN" is to accommodate empty input files.

Answer 2

with gnu awk:

awk '{for(x=1;x<=NF;x++)a[++y]=$x}END{c=asort(a);print "min:",a[1];print "max:",a[c]}'

output:

min: 9
max: 99

without awk:

xargs -n1|sort -n|head or tail -1

e.g.

min:

kent$  echo "20 90 60 30
55 75 80 85
10 15 99 95
55 95 70 20
9  35 85 75"|xargs -n1|sort -n|head -1
9

max:

kent$  echo "20 90 60 30
55 75 80 85
10 15 99 95
55 95 70 20
9  35 85 75"|xargs -n1|sort -n|tail -1
99

you can of course xargs -n1|sort -n then pipe to awk to pick first and last and print in one shot.

Answer 3

If you have GNU awk:

# using array
awk '{x[NR]=$1}END{asort(x);print "max="x[NR],"min="x[1]}' RS=' +|\n' file
max=99 min=9

# No array
awk 'NR==1{m=n=$1}{$1>m?m=$1:m;$1<n?n=$1:n}END{print "max="m,"min="n}' RS=' +|\n' file
max=99 min=9