I need count the number of times in the even lines of the file.txt the letter 'b' or 'B' appears, e.g. for the file.txt like:
everyB or gbnBra
uitiakB and kanapB bodddB
Kanbalis astroBominus
I got the first part but I need to count these b or B letters and I do not know how to count them together
awk '!(NR%2)' file.txt
$ awk '!(NR%2){print gsub(/[bB]/,"")}' file
4
Could you please try following, one more approach with awk written on mobile will try it in few mins should work but.
awk -F'[bB]' 'NR%2 == 0{print (NF ? NF - 1 : 0)}' Input_file
Thanks to #Ed sir for solving zero matches found line problem in comments.
In a single awk:
awk '!(NR%2){gsub(/[^Bb]/,"");print length}' file.txt
gsub(/[^Bb]/,"") deletes every character in the line the line except for B and b.
print length prints the length of the resulting string.
awk '!(NR%2)' file.txt | tr -cd 'Bb' | wc -c
Explanation:
awk '!(NR%2)' file.txt : keep only even lines from file.txt
tr -cd 'Bb' : keep only B and b characters
wc -c : count characters
Example:
With file bellow, the result is 4.
everyB or gbnBra
uitiakB and kanapB bodddB
Kanbalis astroBominus
Here is another way
$ sed -n '2~2s/[^bB]//gp' file | wc -c
Related
Consider the following data in a file file.txt:
$
$
$
FORCE 10 30 40
* 1 5 4
FORCE 11 20 22
* 2 3 0
FORCE 19 25 10
* 16 12 8
.
.
.
I want to print every 2nd element of the third column, starting from line 4, resulting in:
30
20
25
I have tried:
cat file.txt | sed 's/\|/ /' | awk 'NR%2==4 {print $3}'
However, this is not resulting in anything being printed and no errors generated either.
You might use awk checking that the row number > 3 and then check for an even row number with NR%2==0.
Note that you don't have to use cat
awk 'NR > 3 && NR%2==0 {
print $3
}' file.txt
Output
30
20
25
Using sed
$ sed -En '4~2s/([^ \t]*[ \t]+){2}([^ \t]*).*/\2/p' input_file
30
20
25
I have tried:
cat file.txt | sed 's/\|/ /' | awk 'NR%2==4 {print $3}'
However, this is not resulting in anything being printed and no errors
generated either.
You do not need cat whilst using GNU sed as it can read file on its' own, in this case it would be sed 's/\|/ /' file.txt.
You should consider if you need that part at all, your sample input does not have pipe character at all, so it would do nothing to it. You might also drop that part if lines holding values you want to print do not have that character.
Output is empty as NR%2==4 does never hold, remainder of division by x is always smaller than x (in particular case of %2 only 2 values are possible: 0 and 1)
This might work for you (GNU sed):
sed -nE '4~2s/^((\S+)\s*){3}.*/\2/p' file
Turn off implicit printing by setting the -n option and reduce back slashes in regexps by turning on -E.
From the fourth line and then every second line thereafter, capture the third column and print it.
N.B. The \2 represents the last inhabitant of that back reference which in conjunction with the {3} means the above.
Alternative:
sed -n '4,${s/^\(\(\S\+\)\s*\)\{3\}.*/\2/p;n}' file
I want to pipe the output of a command into awk. I want to add that number to every row of a new column in an existing .txt file. The new column should be at the end, and won't necessarily be column 2.
$command 1
4512438
$ input.txt
A
B
C
D
$ desired_ouput.txt
A 4512438
B 4512438
C 4512438
D 4512438
I think I need to do something along the lines of the following. I'm not sure how to designate that the pipe goes into the new column - this awk command will simply add integers to the column.
$ command1 | awk -F, '{$(NF+1)=++i;}1' OFS=, input.txt > desired_ouput.txt
It doesn't seem like you really want to pipe the value to awk. Instead, you want to pass it as a parameter. You could read it from the pipe with something like:
cmd1 | awk 'NR==FNR{a=$0} NR!=FNR{print $0,a}' - input.txt
but it seems much more natural to do:
awk '{print $0,a}' a="$(cmd1)" input.txt
I have a file with 100 columns of data. I want to print the first column and i-th column in 99 separate files, I am trying to use
for i in {2..99}; do awk '{print $1" " $i }' input.txt > data${i}; done
But I am getting errors
awk: illegal field $(), name "i"
input record number 1, file input.txt
source line number 1
How to correctly use $i inside the {print }?
Following single awk may help you too here:
awk -v start=2 -v end=99 '{for(i=start;i<=end;i++){print $1,$i > "file"i;close("file"i)}}' Input_file
An all awk solution. First test data:
$ cat foo
11 12 13
21 22 23
Then the awk:
$ awk '{for(i=2;i<=NF;i++) print $1,$i > ("data" i)}' foo
and results:
$ ls data*
data2 data3
$ cat data2
11 12
21 22
The for iterates from 2 to the last field. If there are more fields that you desire to process, change the NF to the number you'd like. If, for some reason, a hundred open files would be a problem in your system, you'd need to put the print into a block and add a close call:
$ awk '{for(i=2;i<=NF;i++){f=("data" i); print $1,$i >> f; close(f)}}' foo
If you want to do what you try to accomplish :
for i in {2..99}; do
awk -v x=$i '{print $1" " $x }' input.txt > data${i}
done
Note
the -v switch of awk to pass variables
$x is the nth column defined in your variable x
Note2 : this is not the fastest solution, one awk call is fastest, but I just try to correct your logic. Ideally, take time to understand awk, it's never a wasted time
I'm working on an awk one-liner to substitute commas to tabs in a file ( and swap \\N for missing values in preparation for MySQL select into).
The following link http://www.unix.com/unix-for-dummies-questions-and-answers/211941-awk-output-field-separator.html (at the bottom) suggest the following approach to avoid looping through the variables:
echo a b c d | awk '{gsub(OFS,";")}1'
head -n1 flatfile.tab | awk -F $'\t' '{for(j=1;j<=NF;j++){gsub(" +","\\N",$j)}gsub(OFS,",")}1'
Clearly, the trailing 1 (can be a number, char) triggers the printing of the entire record. Could you please explain why this is working?
SO also has Print all Fields with AWK separated by OFS , but in that post it seems unclear why this is working.
Thanks.
Awk evaluates 1 or any number other than 0 as a true-statement. Since, true statements without the action statements part are equal to { print $0 }. It prints the line.
For example:
$ echo "hello" | awk '1'
hello
$ echo "hello" | awk '0'
$
I have a file with a single line in it that has a record that is deliminted by semi-colons. So far I have figured out that I can use tr by issuing:
tr ';' '\n' < t
However since the record has 140 fields, I'd like to be able to show the field count when displaying such as the following:
1 23
2 324234
3 AAA
.
.
140 Blah
Help is greatly appreciated!
tr \; '\n' <t|nl
or
awk -v RS=';' '$1=++i" "$1' file
test:
kent$ echo "a;b;c;d"|awk -v RS=';' '$1=++i" "$1'
1 a
2 b
3 c
4 d
You could just run it through cat -n.
tr \; '\n' < t | cat -n
Since this is tagged awk, you could do it that way, too; it's just a little wordier:
awk -F\; '{for (i=1;i<=NF;++i) { print i" "$i }}'
In shell you can use IFS to specify a field separator like so,
IFS=";"
i=0
for s in $(<file)
do
((i++))
echo $i $s
done