Shell Programming and Scripting

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 awk -F" " '{ if(!($1 in max) || (max[$1]<$3)) max[$1]=$3 ; count[$1]++ } END { for(element in max) printf("%s %.2f\n", element, max[element] ) } ' file.txt

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 cat file.txt | awk -F " " 'BEGIN{if(a[$1]<$2) { a[$1]=$3;}}END {for(i in a){print i " " a[i];}}'

awk '
        {
                if ( A[$1] < $2 )
                        A[$1] = $2
        }
        END {
                for ( k in A )
                        print k, A[k]
        }
' file

awk 'NR==FNR{a[$1]=$2;} ($1 in a){if(a[$1]<$2) {a[$1]=$2}} END{for(j in a){print j OFS a[j]}}' check_2nd_column_max_value12111 check_2nd_column_max_value12111

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awk '{if($2 > a[$1]) {a[$1] = $2}} END {for(x in a) {print x, a[x]}}' file