awk with For loop


Login or Register to Reply

 
Thread Tools Search this Thread
# 1  
awk with For loop

Hi

My Requirement is to take the sum of each column
below is the input file.
Code:
1 2 3 4
1 2 3 4
1 2 3 4

Initial i was using below command to achieve my desired result. however this was adding the row and not column.
i am not able understand why this is happening
Code:
 awk '{for(i=1;i<=NF;i++)x+=$i;print x;x=0}' M.txt  ----->1

After many hit&trial attempt and googling i am able to sum up the column . which is mentioned below.
Code:
 awk '{for(i=1;i<=NF;i++) sum[i]+=$i;};END {for (k=1;k<=NF;k++) print sum[k];}' t.txt ------->2

Also not able to understand why using this bracket
Code:
 [] is giving correct solution.

although i have achieved my target but not able to understand the detail working of the command.
as in both the command i am using NF but still in command 1 it sum up the row and not column.

scriptor
# 2  
awk works in a way that it reads one input record (one line by default), executes the entire script on that line, and the proceeds to the next record.

In command 1, for every single input line you are summing up all fields in that line into a scalar variable, and then print (and reset) that variable.
In command 2, in lieu of using a scalar variable, you are using an array (indicated by the square brackets) indexed by the field No. to sum up the respective fields' values for ALL input lines, and print the sums in the END section.
See the difference now? Good reading is man awk.
Login or Register to Reply

|
Thread Tools Search this Thread
Search this Thread:
Advanced Search

More UNIX and Linux Forum Topics You Might Find Helpful
awk !seen[$]++ in else loop
ksenia
Hi all, I was searching the net for a solution for my problem... unfortunately nothing so far. I want to sort on more than on column tab delimited file and keep the line if in the column I sort there is no value, but for those who have a value I want them only unique. I have tried the...... UNIX for Beginners Questions & Answers
5
UNIX for Beginners Questions & Answers
awk programming -Passing variable to awk for loop
ctrld
Hi All, I am new to AWK programming. I have the following for loop in my awk program. cat printhtml.awk: BEGIN -------- <some code here> END{ ----------<some code here> for(N=0; N<H; N++) { for(M=5; M<D; M++) print "\t" D ""; } ----- } ...... Shell Programming and Scripting
2
Shell Programming and Scripting
awk loop using array:wish to store array values from loop for use outside loop
klane
Here's my code: awk -F '' 'NR==FNR { if (/time/ && $5>10) A=$2" "$3":"$4":"($5-01) else if (/time/ && $5<01) A=$2" "$3":"$4-01":"(59-$5) else if (/time/ && $5<=10) A=$2" "$3":"$4":0"($5-01) else if (/close/) { B=0 n1=n2; ...... Shell Programming and Scripting
2
Shell Programming and Scripting
awk loop and using shell in awk
xshang
Hi, everyone! I have a file, when I print its $1 out it show several strings like this: AABBCC AEFJKLFG FALEF FAIWEHF What I want to do is that, after output of each record, search the string in all files in the same folder, print out the record and file name. This is what I want...... Shell Programming and Scripting
4
Shell Programming and Scripting
Comparison and editing of files using awk.(And also a possible bug in awk for loop?)
linuxkid
I have two files which I would like to compare and then manipulate in a way. File1: pictures.txt 1.1 1.3 dance.txt 1.2 1.4 treehouse.txt 1.3 1.5 File2: pictures.txt 1.5 ref2313 1.4 ref2345 1.3 ref5432 1.2 ref4244 dance.txt 1.6 ref2342 1.5 ref2352 1.4 ref0695 1.3 ref5738 1.2...... Shell Programming and Scripting
1
Shell Programming and Scripting
Linux and UNIX

Linux is a family of open source Unix-like operating systems based on the Linux kernel. The Linux kernel is an operating system kernel first released by Linus Torvalds on 17 September 1991. Linux distributions include the Linux kernel, system software and libraries. Popular free open source Linux distributions include Debian, Fedora, and Ubuntu. Commercial Linux distributions include Red Hat Enterprise Linux and SUSE Linux Enterprise Server. Linux may be freely modified and redistributed. Anyone on the planet may create a Linux distribution for any purpose.
Unix (trademarked as the UNIX certification mark) is a very mature family of multitasking, multiuser computer operating systems that evolved from the original AT&T Unix. Unix development starting in the 1970s by legendary Bell Labs programmers Ken Thompson, Dennis Ritchie, and others. Unix was first targeted for the Bell System and AT&T licensed Unix to outside parties. In the 1970s time period, this lead to a variety of for-profit as well as not-for-profit Unix variants.
In the early days, this included the University of California, Berkeley (BSD), Microsoft (Xenix), IBM (AIX), and Sun Microsystems (Solaris). In the early 1990s, AT&T sold their Unix rights to Novell. In 1995 Novell sold their Unix business to the Santa Cruz Operation (SCO). The UNIX trademark was passed to The Open Group, a "neutral" industry consortium. The Open Group promoted the use of the UNIX trademark for certified operating systems that comply with the Single UNIX Specification (SUS). In 2014 Apple's macOS became the Unix version with the largest global install base and macOS remains the largest Unix-user base today.
Please enjoy and help our forum community by "showing your work" and posting your code, even when your code is not working as expected. To help others help you, please wrap your code blocks, sample input, sample output, error messages, and other data in CODE tags and wrap your short commands and short data objects in ICODE tags. We were all beginners in the beginning. If you have any questions about how to register or how to post, please contact us in Live Chat. Thank you and enjoy this "forever free" technical support community for UNIX, Linux and computer information technology in general.