Use awk to find average of a column [duplicate]

by 
awk '{ sum += $2; n++ } END { if (n > 0) print sum / n; }'

Add the numbers in $2 (second column) in sum (variables are auto-initialized to zero by awk) and increment the number of rows (which could also be handled via built-in variable NR). At the end, if there was at least one value read, print the average.

awk '{ sum += $2 } END { if (NR > 0) print sum / NR }'

If you want to use the shebang notation, you could write:

#!/bin/awk

{ sum += $2 }
END { if (NR > 0) print sum / NR }

You can also control the format of the average with printf() and a suitable format ("%13.6e\n", for example).

You can also generalize the code to average the Nth column (with N=2 in this sample) using:

awk -v N=2 '{ sum += $N } END { if (NR > 0) print sum / NR }'

More Related Contents:

  1. How can I manipulate text in bash? [closed]
  2. How do I use shell variables in an awk script?
  3. How can I do a recursive find/replace of a string with awk or sed?
  4. Bash tool to get nth line from a file
  5. How to merge every two lines into one from the command line?
  6. bash: shortest way to get n-th column of output
  7. awk in bash with ls and variable
  8. Remove first N lines of a file in place in unix command line
  9. How to add to the end of lines containing a pattern with sed or awk?
  10. Sort a text file by line length including spaces
  11. How to make awk ignore the field delimiter inside double quotes? [duplicate]
  12. Parse out key=value pairs into variables
  13. Specify other flags in awk script header
  14. Check if all of multiple strings or regexes exist in a file
  15. Parsing a CSV file using gawk
  16. Split CSV files into smaller files but keeping the headers?
  17. Bash: Parse CSV with quotes, commas and newlines
  18. How to remove double-quotes in jq output for parsing json files in bash?
  19. How to find/replace and increment a matched number with sed/awk?
  20. find difference between two text files with one item per line [duplicate]
  21. Grep output with multiple Colors?
  22. Using grep to search for hex strings in a file
  23. How to append a string at end of a specific line in a file in bash [duplicate]
  24. How to strip out all of the links of an HTML file in Bash or grep or batch and store them in a text file
  25. Parse HTML using shell
  26. How to get the PID of a process in a pipeline
  27. using bash (sed/awk) to extract rows AND columns in CSV files?
  28. What is the shortest way to get n-th column of an output?
  29. How to grep for case insensitive string in a file?
  30. How can I format the output of a bash command in neat columns

Leave a Comment