Sponsored Content
Top Forums Shell Programming and Scripting Tip: alternative for NR==FNR in awk Post 302911611 by Don Cragun on Friday 1st of August 2014 04:32:13 PM
Old 08-01-2014
Quote:
Originally Posted by MadeInGermany
Thanks Don,
... ... ...
BTW most awk versions want if (... ~ "="). While all accept (... ~ /=/) outside a {block}
Thanks for the warning.

The standards say that the right hand operand of the ~ and !~ operators can always be a string containing an ERE or an ERE token (i.e., /ERE/). But, if there is an ambiguity as to whether a / is a division operator or part of an ERE token, awk is supposed to assume it is a division operator. In a simple if statement like this, there shouldn't be any ambiguity.
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Awk: different between NR and FNR

As I know: FNR: The ordinal number of the current record in the current file. NR: The ordinal number of the current record from the start of input. I don't understand really differency between NR and FNR. Who can explain it for me? And give me an example. Thanks (1 Reply)
Discussion started by: anhtt
1 Replies

2. Shell Programming and Scripting

awk NR==FNR compare 2 files produce a 3rd

hi, i have two files, both with 3 columns, the 3rd column has common values between the two files and i want to produce a 3rd file with 4 columns. file 1 a, ,b c file 2 a, b ,d I want to compare the 3rd value and if a match print to file 3 with the 3 columns from the first file... (11 Replies)
Discussion started by: borderblaster
11 Replies

3. UNIX for Dummies Questions & Answers

Multiple Column print after lookup using NR==FNR (awk)

foo.txt FAMID IID AFF SEX Group AgeCat Dis1 Dis2 Dis3 Dis4 Dis5 Dis6 Dis6 AMD0001 Mayo_49542 1 2 AMD 8 1 1 1 1 1 1 1 AMD0002 Mayo_49606 1 1 AMD 3 1 1 1 1 ... (7 Replies)
Discussion started by: genehunter
7 Replies

4. UNIX for Dummies Questions & Answers

awk NR==FNR output control

Hi Guys, I have two files: f1: A B C D E F G H f2: A X Y Z f1 has 48000 lines, and f2 has 68. I have been matching f1 $3 to f2 $1, and getting f3: A A B C D E F G I would like f3 too look like this: A X Y Z A B C D E F G (2 Replies)
Discussion started by: heecha
2 Replies

5. Shell Programming and Scripting

Awk FNR==NR question

awk -F'' 'FNR==NR {a=$2; next} {$1=a} 1' $useralias ${entries} >> ${entries}_2 Hi, Is there anyway to alter this command so that if it does not find a match it will just leave the line alone instead of replacing what it doesn't find with a blank space? (4 Replies)
Discussion started by: Jazmania
4 Replies

6. Shell Programming and Scripting

Quick awk tip :)

how do i "awk" the date after the from only to compare it on a if statement later . filename example: server1-ips-ultranoob-ok_From_2012_21_12-23:40:23_To_2012_21_12-23:49:45.zip what i want o do is compare only the date from the string in "From_2012_21_12" in this case i only want the... (4 Replies)
Discussion started by: drd0spt
4 Replies

7. Shell Programming and Scripting

Help with Alternative for NR==FNR

Hi, I have an issue with the below script nawk 'NR==FNR{a=$4" "$5}NR>FNR{print NF?$0:a"\n";if(/^cn:/) x=$0}' FS="" in1.txt in2.txt > out1.txt It is taking too long to get a string from in1.text, search for the string in in2.txt and create a new file out1.txt. Is there any alternative way we... (1 Reply)
Discussion started by: Samingla
1 Replies

8. Shell Programming and Scripting

awk --> selective printout with FNR

Hi everybody! need some awk-support. i want a line-selective printout of a file. wat i normally will do with ... awk ' FNR==8' sample.txt But now i need the data from line 8, 10 and the following data from line13 to 250 wich is not end of the file. I tried allready to combine it but without... (2 Replies)
Discussion started by: IMPe
2 Replies

9. Shell Programming and Scripting

Explanation of FNR in this awk script

To merge mutiple *.tab files as: file1.tab rs1 A A rs2 A A rs3 C C rs4 C Cfile2.ind rs1 T T rs2 T T rs3 G G rs4 G Gand file3.tab rs1 B B rs2 B B rs3 L L rs4 L LOutput: file1.tab file2.tab file3.tab AA TT BB AA TT BB CC GG LL CC GG ... (4 Replies)
Discussion started by: yifangt
4 Replies

10. Shell Programming and Scripting

Awk: Assigning a variable to be the value of FNR at a certain line

Sorry for the probably strangely worded title but I don't really know how else to put it. Background context: Post processing LAMMPS simulation data. tl;dr: I'm making two spheres collide, every defined timestep the simulation outputs a bunch of data including total energy of the particles,... (10 Replies)
Discussion started by: ThomasP
10 Replies
ALTER 
OPERATOR(7) SQL Commands ALTER OPERATOR(7) NAME
ALTER OPERATOR - change the definition of an operator SYNOPSIS
ALTER OPERATOR name ( { lefttype | NONE } , { righttype | NONE } ) OWNER TO newowner DESCRIPTION
ALTER OPERATOR changes the definition of an operator. The only currently available functionality is to change the owner of the operator. You must own the operator to use ALTER OPERATOR. To alter the owner, you must also be a direct or indirect member of the new owning role, and that role must have CREATE privilege on the operator's schema. (These restrictions enforce that altering the owner doesn't do anything you couldn't do by dropping and recreating the operator. However, a superuser can alter ownership of any operator anyway.) PARAMETERS
name The name (optionally schema-qualified) of an existing operator. lefttype The data type of the operator's left operand; write NONE if the operator has no left operand. righttype The data type of the operator's right operand; write NONE if the operator has no right operand. newowner The new owner of the operator. EXAMPLES
Change the owner of a custom operator a @@ b for type text: ALTER OPERATOR @@ (text, text) OWNER TO joe; COMPATIBILITY
There is no ALTER OPERATOR statement in the SQL standard. SEE ALSO
CREATE OPERATOR [create_operator(7)], DROP OPERATOR [drop_operator(7)] SQL - Language Statements 2010-05-14 ALTER OPERATOR(7)
All times are GMT -4. The time now is 03:42 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy