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1. Shell Programming and Scripting
Judi # cat File1
judi /export/home 76
judi /usr 83
judi #
judi # cat File2
judi /export/home 79
judi /usr 82
judi #
if COLUMN3 of File2 is greater that COLUMN3 of File1, then print File2's lines
juid /export/home 79
Code tags please (2 Replies)
Discussion started by: judi
2 Replies
2. Shell Programming and Scripting
hello everybody
I have 2 files the
file1 has 10 columns and the form:
...
110103 0802 1.16 38 20.16 22 1.21 8.77 0.00 20
120103 0832 23.40 38 22.10 21 46.35 10.17 0.00 28
120103 1413 45.00 38 24.50 21 48.85 7.89 0.00 38
130103 1112 23.40 38 22.10 21 48.85 ... (5 Replies)
Discussion started by: phaethon
5 Replies
3. Shell Programming and Scripting
Dear Unix experts,
I have got a file where I would like to compare the values of second column if first column is same in such a way that the difference between the values is >50. If not, I would like to discard both values.
For example, my input file looks like -
comp275_c0_seq2 73... (7 Replies)
Discussion started by: utritala
7 Replies
4. Shell Programming and Scripting
Hi,
I want to compare two columns from file1 with another two column of file2 and print matched and unmatched column like this
File1
1 rs1 abc
3 rs4 xyz
1 rs3 stu
File2
1 kkk rs1 AA 10
1 aaa rs2 DD 20
1 ccc ... (2 Replies)
Discussion started by: justinjj
2 Replies
5. Shell Programming and Scripting
- I have two files (File 1 and File 2) and the contents of the files are mentioned below.
- I am trying to compare the values of Column1 of File1 with Column1 of File2. If a match is found, print the corresponding value from Column2 of File1 in Column5 of File2.
- I tried to modify and use... (10 Replies)
Discussion started by: Santoshbn
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6. Shell Programming and Scripting
I would like to compare the values of 2nd column of consecutive lines of same file in such a way so that if the difference between first value and second value is more than 100 it should print complete line else ignore line.
Input File
==========
PDB 2500
RTDB 123
RTDB-EAGLE 122
VSCCP 2565... (4 Replies)
Discussion started by: manuswami
4 Replies
7. Shell Programming and Scripting
Hi,
I want to compare the columns of two files excluding column 2 from both the files. I tried this awk command.
awk -F":" 'NR==FNR{++a;next} !(a)' file1.txt file2.txt
.
Example: File1.txt
123:09-15-2011:abc:123456
123:09-15-2011:abc:234567
123:09-15-2011:abc:345678
... (5 Replies)
Discussion started by: shell_newbie
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8. UNIX for Dummies Questions & Answers
I have a text file that has three columns. But at the end of the text file, there are trailing lines that have missing second and third columns:
4 0.04972604 KLHL28
4 0.0497332 CSTB
4 0.04979822 AIF1
4 0.04983331 DECR2
4 0.04990344 KATNB1
4
4
4
4
How can I remove the trailing... (3 Replies)
Discussion started by: evelibertine
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9. Shell Programming and Scripting
Hello. I have two files. FILE1 was extracted from FILE2 and modified thanks to help from this post. Now I need to replace the extracted, modified lines into the original file (FILE2) to produce the FILE3.
FILE1
1466 55.27433 14.72050 -2.52E+03 3.00E-01 1.05E+04 2.57E+04
1467 55.27433... (1 Reply)
Discussion started by: jm4smtddd
1 Replies
10. Shell Programming and Scripting
Hi all
I am trying to scan a file that has 3 columns:
red blue 123351
red blue 848655
red blue 126354
red blue 023158
black white 654896
red blue 650884
I want an output that sums the rows that have matching columns 1 and 2 :wall:
red blue has 5 entries
black white has 1 entry
... (4 Replies)
Discussion started by: reno
4 Replies
A2P(1) Perl Programmers Reference Guide A2P(1)
NAME
a2p - Awk to Perl translator
SYNOPSIS
a2p [options] [filename]
DESCRIPTION
A2p takes an awk script specified on the command line (or from standard input) and produces a comparable perl script on the standard
output.
OPTIONS
Options include:
-D<number>
sets debugging flags.
-F<character>
tells a2p that this awk script is always invoked with this -F switch.
-n<fieldlist>
specifies the names of the input fields if input does not have to be split into an array. If you were translating an awk script that
processes the password file, you might say:
a2p -7 -nlogin.password.uid.gid.gcos.shell.home
Any delimiter can be used to separate the field names.
-<number>
causes a2p to assume that input will always have that many fields.
-o tells a2p to use old awk behavior. The only current differences are:
o Old awk always has a line loop, even if there are no line actions, whereas new awk does not.
o In old awk, sprintf is extremely greedy about its arguments. For example, given the statement
print sprintf(some_args), extra_args;
old awk considers extra_args to be arguments to "sprintf"; new awk considers them arguments to "print".
"Considerations"
A2p cannot do as good a job translating as a human would, but it usually does pretty well. There are some areas where you may want to
examine the perl script produced and tweak it some. Here are some of them, in no particular order.
There is an awk idiom of putting int() around a string expression to force numeric interpretation, even though the argument is always
integer anyway. This is generally unneeded in perl, but a2p can't tell if the argument is always going to be integer, so it leaves it in.
You may wish to remove it.
Perl differentiates numeric comparison from string comparison. Awk has one operator for both that decides at run time which comparison to
do. A2p does not try to do a complete job of awk emulation at this point. Instead it guesses which one you want. It's almost always
right, but it can be spoofed. All such guesses are marked with the comment ""#???"". You should go through and check them. You might
want to run at least once with the -w switch to perl, which will warn you if you use == where you should have used eq.
Perl does not attempt to emulate the behavior of awk in which nonexistent array elements spring into existence simply by being referenced.
If somehow you are relying on this mechanism to create null entries for a subsequent for...in, they won't be there in perl.
If a2p makes a split line that assigns to a list of variables that looks like (Fld1, Fld2, Fld3...) you may want to rerun a2p using the -n
option mentioned above. This will let you name the fields throughout the script. If it splits to an array instead, the script is probably
referring to the number of fields somewhere.
The exit statement in awk doesn't necessarily exit; it goes to the END block if there is one. Awk scripts that do contortions within the
END block to bypass the block under such circumstances can be simplified by removing the conditional in the END block and just exiting
directly from the perl script.
Perl has two kinds of array, numerically-indexed and associative. Perl associative arrays are called "hashes". Awk arrays are usually
translated to hashes, but if you happen to know that the index is always going to be numeric you could change the {...} to [...].
Iteration over a hash is done using the keys() function, but iteration over an array is NOT. You might need to modify any loop that
iterates over such an array.
Awk starts by assuming OFMT has the value %.6g. Perl starts by assuming its equivalent, $#, to have the value %.20g. You'll want to set
$# explicitly if you use the default value of OFMT.
Near the top of the line loop will be the split operation that is implicit in the awk script. There are times when you can move this down
past some conditionals that test the entire record so that the split is not done as often.
For aesthetic reasons you may wish to change index variables from being 1-based (awk style) to 0-based (Perl style). Be sure to change all
operations the variable is involved in to match.
Cute comments that say "# Here is a workaround because awk is dumb" are passed through unmodified.
Awk scripts are often embedded in a shell script that pipes stuff into and out of awk. Often the shell script wrapper can be incorporated
into the perl script, since perl can start up pipes into and out of itself, and can do other things that awk can't do by itself.
Scripts that refer to the special variables RSTART and RLENGTH can often be simplified by referring to the variables $`, $& and $', as long
as they are within the scope of the pattern match that sets them.
The produced perl script may have subroutines defined to deal with awk's semantics regarding getline and print. Since a2p usually picks
correctness over efficiency. it is almost always possible to rewrite such code to be more efficient by discarding the semantic sugar.
For efficiency, you may wish to remove the keyword from any return statement that is the last statement executed in a subroutine. A2p
catches the most common case, but doesn't analyze embedded blocks for subtler cases.
ARGV[0] translates to $ARGV0, but ARGV[n] translates to $ARGV[$n-1]. A loop that tries to iterate over ARGV[0] won't find it.
ENVIRONMENT
A2p uses no environment variables.
AUTHOR
Larry Wall <larry@wall.org>
FILES
SEE ALSO
perl The perl compiler/interpreter
s2p sed to perl translator
DIAGNOSTICS
BUGS
It would be possible to emulate awk's behavior in selecting string versus numeric operations at run time by inspection of the operands, but
it would be gross and inefficient. Besides, a2p almost always guesses right.
Storage for the awk syntax tree is currently static, and can run out.
perl v5.18.2 2014-01-06 A2P(1)