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How to read n number of lines from a file

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# 22  
Old 11-03-2009
hi everybody

i have one shell scripting which calculate average value for columns
this is the script


echo "enter file name"
read file

cat $file

awk 'BEGIN {FS=OFS=" "} { for (i=1; i<=NF; i++) sum[i] += $i; j=NF }
END { printf "%s%s", "------------------", "\nAvg"; for (i=1; i <= j; i++) printf "%s%s", OFS, sum[i]/NR; printf "\n"; }' $file

it gives the output like this
enter file name
1 5 3 4 6 8
5 5 7 9 0 1
4 6 4 4 6 2
6 7 8 12 3 4
Avg 4 5.75 5.5 7.25 3.75 3.75

but i want to do calculaton for average in row wise so that my output will look like this

enter file name
1 5 3 4 6 8 = 4.5
5 5 7 9 0 1 = 4.5
4 6 4 4 6 2 = 4.333333333
6 7 8 12 3 4 = 6.666666667

Any help is thankfully appericiated

Last edited by Franklin52; 02-16-2010 at 07:02 AM.. Reason: Please use code tags!
# 23  
Old 11-03-2009
Try this...

awk '{print $0,"=",($1+$2+$3+$4+$5+$6)/6}' file

# 24  
Old 11-03-2009
tanx!!! it worked

but one thing i can have either more than 6columns or less than that also same thing for no of rows also

for eg my output should be like this
enter file name
1 5 3 = 3
5 5 7 9 0 1 = 4.5
4 6 4 4 6  = 4.8
6 7 8 12 3 4 55 = 13.571428571

once again tanx in advance!!

Last edited by Franklin52; 02-16-2010 at 07:02 AM.. Reason: Please use code tags!
# 25  
Old 11-03-2009

nawk 'NF{for (i=1;i<=NF;i++) {x+=$i} ; print $0," =",x/NF ; x=0}' input_file

# 26  
Old 11-03-2009
hi ahmad.diab,

tanx for ur code but the code throws me error saying that

nawk: command not found

help me plzzzz

thanks again in advance!!!!
# 27  
Old 11-04-2009
use gawk or /usr/xpg4/bin/awk instead of nawk.

# 28  
Old 11-04-2009
Hi ahmad.diab,

I replaced gawk instead nawk. Thanks , it works well. But can u plz explain me why nawk not worked , i need the whole script explanation.????

Tanx once again!!!

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