CODEWITHSUNDEEP
linuxbashawk
Sandra Schlichting
Sandra Schlichting

Reputation: 25986

awk function syntax error?

Can someone see why I get

awk: cmd. line:8:   function mma(num) {
awk: cmd. line:8:   ^ syntax error
awk: cmd. line:8:   function mma(num) {
awk: cmd. line:8:                     ^ syntax error

from this script?

echo "0.24 0.21 0.22 1/1282 10953" | awk '{

  min=""
  max=""
  avg=""

  # find min, max, avg
  function mma(num) {
    if(min==""){min=max=$1};
    if($1>max) {max=$1};
    if($1<min) {min=$1};
    total+=$1;
    count+=1;
    avg=total/count;
  }

  mma($1)
  mma($2)
  mma($3)

  print avg, max, min
}'

Upvotes: 0

Views: 759

Answers (1)

kvantour
kvantour

Reputation: 26471

Definitions of functions can appear anywhere between the rules of an awk program. From the POSIX standard :

The awk language also provides user-defined functions. Such functions can be defined as:

function name([parameter, ...]) { statements }

A function can be referred to anywhere in an awk program; in particular, its use can precede its definition. The scope of a function is global. <snip> Function definitions can appear anywhere in the program where a pattern-action pair is allowed.

This means a valid awk program looks like :

( pattern1 ) { action1 }
function name([parameter, ...]) { statements }
( pattern2 ) { action2 }
...

In your original code, you wrote the incorrect

( pattern ) { function name([paramter, ...]) { statements }
             action }

So the corrected version of your awk part would be:

awk 'function mma(num) {
        if(min==""){min=max=$1};
        if($1>max) {max=$1};
        if($1<min) {min=$1};
        total+=$1;
        count+=1;
        avg=total/count;
     }
     { min=""; max=""; avg=""
       mma($1); mma($2); mma($3)
       print avg, max, min
     }'

update: from the comments, it might be more useful to use

awk '{ avg=($1+$2+$3)/3; min=avg; max=avg;
       min=($1<min) ? $1 : min; max=($1>max) ? $1 : max
       min=($2<min) ? $2 : min; max=($2>max) ? $2 : max
       min=($3<min) ? $3 : min; max=($3>max) ? $3 : max
       print avg,max, min } ' /proc/loadavg

However, this is questionable as taking the average of averages is very ...

Also interesting might be the sar command.

Upvotes: 5

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