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How to read n number of lines from a file

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Top Forums Shell Programming and Scripting How to read n number of lines from a file
# 29  
Old 11-04-2009
Quote:
Originally Posted by varsha
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!!!
Code:
nawk will only work on Solaries machines GAWK is the standard (GUNU awk) and better one which will work on Linux systems.

BR

# 30  
Old 11-09-2009
Help!!
Hello all,

I have a script which calculate avg for columnwise I attaced the script below

script
Code:
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

output
Code:
enter file name
vfile
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 when there is any disordered no of row for eg 1st col may have 5rows 2nd column have 4rows means it is calculating only 1st col

sample output
Code:
enter file name
vfile
1 5 3 4 6 8 9 9
5 5 7 9 0 1  1
4 6 4 4 6 2
6 7 8 12 3 4
7    9
------------------
Avg 4.6 6.4


but i want the output like more over in the above o/p instead of 6.2 its printing 6.4

Code:
enter file name
vfile
1 5 3 4 6 8 9 9
5 5 7 9 0 1 1
4 6 4 4 6 2
6 7 8 12 3 4
7    9
------------------
Avg 4.6 5.75 6.2 7.25 3.75 3.75 5 9


I belive my promblem would have reached u plzzzzzzzz kindly help meSmilieSmilieSmilie


Thanks!!!!SmilieSmilie
Last edited by Franklin52; 02-16-2010 at 07:03 AM.. Reason: Please use code tags!
# 31  
Old 11-09-2009
code:-

Code:
gawk '{for (i=1;i<=NF;i++){a[i]+=$i;b[i]++ ; if(nf < NF) {nf=NF}  } }

END{printf "Avrg  " ; for (i in a) {printf "%s %s",a[nf+1-i]/b[nf+1-i],( i < nf ) ? " " : "\n" }}
'   file.txt

SmilieSmilieSmilieSmilie
# 32  
Old 11-09-2009
Help!!
Instead of giving output like this

Code:
enter file name
vfile
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


its giving some other result(output)
Code:
enter file name
vfile

1 5 3 4 6 8
5 5 7 9 0 1
4 6 4 4 6 2
6 7 8 12 3 4

Avrg  5.5  5.75  4 
3.75  3.75  7.25



Plz hepl meSmilieSmilieSmilieSmilie


Thanks again!!SmilieSmilieSmilie
Last edited by Franklin52; 02-16-2010 at 07:04 AM.. Reason: Please use code tags!
# 33  
Old 11-09-2009
modification in below:-

Code:
gawk '{for (i=1;i<=NF;i++){a[i]+=$i;b[i]++ ; if(nf <= NF) {nf=NF}  } }

END{printf "Avrg  " ; for (i in a) {printf "%s %s",a[nf+1-i]/b[nf+1-i],( i <= nf ) ? " " : "\n" }}
'   file.txt



---------- Post updated at 12:24 PM ---------- Previous update was at 11:20 AM ----------
Quote:
Originally Posted by ahmad.diab
modification in below:-

Code:
gawk '{for (i=1;i<=NF;i++){a[i]+=$i;b[i]++ ; if(nf <= NF) {nf=NF}  } }

END{printf "Avrg  " ; for (i in a) {printf "%s %s",a[nf+1-i]/b[nf+1-i],( i <= nf ) ? " " : "\n" }}
'   file.txt

Code:
note:- if the averages are not in order use /usr/xpg4/bin/awk instead of gawk

SmilieSmilieSmilieSmilieSmilieSmilieSmilie
# 34  
Old 11-10-2009
Help!!
hello.....

In result the averages are not in order so instead of gawk i used /usr/xpg4/bin/awk but it throws me error showing No such file or directory



Help meSmilieSmilieSmilieSmilie





ThanksSmilieSmilieSmilieSmilieSmilieSmilie
# 35  
Old 11-10-2009
Ignore this ..Supposed to be in another thread

---------- Post updated at 12:24 PM ---------- Previous update was at 12:19 PM ----------

Hi Try this:

Added if ( j != count-1 ) to get next line and works good....

awk -v count=$n '{k = $1; getline; for (j=1; j<count; j++) {if ( $1 > k ) k = $1
; if ( j != count-1 ) getline;} print k}' $file...

Sorry i didnot see that it is solved...
Last edited by bittoo; 11-10-2009 at 03:03 AM..
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