Commands by italo

Commands by italo (1)

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Take a file as input (two columns data format) and sum values on the 2nd column for all lines that have the same value in 1st column

Example: cat <<EOF >/tmp/foo 5 45 80 35 4 10 80 15 80 10 4 10 5 20 EOF awk '{a[$1] += $2} END { for (i in a) {print i "=" a[i]}}' /tmp/foo 80=60 4=20 5=65
This is sample output - yours may be different.
1

awk '{a[$1] += $2} END { for (i in a) {print i " " a[i]}}' /path/to/file

italo · 2010-04-11 02:28:09 4

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