topic ave and max in Operating System - HP-UX

ave and max

Lexxx — Wed, 14 Feb 2007 01:54:15 GMT

Hi Guys,
I have a file which contains numbers (some of them decimals). For each file has different word count (wc -l). I computed for each the average and maximum value. I did use for loops like for i in `cat file`
do
x = `expr $x + i | bc -l`
done
x is at initial zero then I use it as well by checking max by "if" logic.
But it requires time so I may ask if you have any idea how can I use awk in it for the average and maximum values in that file.
Will appreciate your help. Regards....

Re: ave and max

Dennis Handly — Wed, 14 Feb 2007 03:53:15 GMT

Assuming one per line:
awk '
BEGIN { max=-2000000000; sum=0; count=0 }
{
count++
sum+=$1
if ($1 > max)
max = $1
}
END {
print "average:", sum/count
print "max:", max
} ' file

I suppose NR could be used instead of count.

Re: ave and max

Arturo Galbiati — Wed, 14 Feb 2007 05:49:35 GMT

Hi,
assuming one value per line:
(/> is my prompt)

/> cat f1
1.5
2
4
0.5
0

To get what you need:
/> sort -nk1 f1|awk '{t+=$1};END {print "Total=" t " Lines=" NR " AVG=" t/NR " MAX=" $1}';
Total=8 Lines=5 AVG=1.6 MAX=4

I print Total and Lines for debug, but you can avoid this.

HTH,
Art

Re: ave and max

Peter Nikitka — Wed, 14 Feb 2007 13:17:04 GMT

Hi,

I don't understand what you mean by
>>
For each file has different word count (wc -l)
<<

Do you have to parse several files, all containing numbers you want to do calculation with? You can use the awk internal variables 'FILENAME' and 'FNR' for this.
Next: is there only one number per line or do you have multiple entries per line? You would have to
- loop over all (valid?) fields of line in that case (e.g. for(i=1;i<=NF;i++) ...).
- add the number of fields instead of using FNR (e.g. num+=NF)
in that case.

awk 'BEGIN {max="undef"}
FILENAME && FILENAME != lastf {printf("max=%s avg=%s\n", max,sum/FNR); max="undef"; sum=0 }
{lastf=FILENAME; sum+=$1; if(max=="undef") max=$1; else if($1>max) max=$1 }
END {printf("max=%s avg=%s\n", max,sum/FNR)}' file1 file2 ...

mfG Peter

Re: ave and max

Dennis Handly — Thu, 15 Feb 2007 04:29:00 GMT

>Peter: I don't understand what you mean by

I assumed that the script would have to calculate the number of records and couldn't be a constant.