Print out only the first column in a non-standard CSV file - csv

I have a file that is delimited by comma ",", but some rows have only one column, and some rows have multiple columns separated by ",". For example:
NM_001066
NM_015378,NM_018156
NM_001006624,NM_001006625,NM_006474,NM_198389
As you can see above, the third line has 4 columns delimited by ",", but I only need to get the first column in every line.
I tried to use awk: cat fileName.txt | awk '{print $1}', but it does not work. I am looking for help with this. Thank you!

I guess you're looking for this:
awk -F, '{print $1}' file.txt
-F, tells awk to use comma as the field separator.
In this simple case, the same thing is simpler with cut:
cut -f1 -d, file.txt

you are close:
awk -F, '{print $1}' file
or
awk -F, '$0=$1' file

Related

AWK using file to remove csv rows

I have the following csv:
old.csv
irrelevant,irrelevant,Abc#gmail.com,irrelevant
irrelevant,irrelevant,zyx#gmail.com,irrelevant
irrelevant,irrelevant,yZ#yahoo.com,irrelevant
irrelevant,irrelevant,that#email.com,irrelevant
irrelevant,irrelevant,this#email.com,irrelevant
irrelevant,irrelevant,def#gmail.com,irrelevant
irrelevant,irrelevant,anoTher#mydomain.com,irrelevant
that I need to remove the rows containing emails from this file:
remove.txt
abc#gmail.com
yz#yahoo.com
this#email.com
another#mydomain.com
And I need the output to be this:
new.csv
irrelevant,irrelevant,zyx#gmail.com,irrelevant
irrelevant,irrelevant,that#email.com,irrelevant
irrelevant,irrelevant,def#gmail.com,irrelevant
I've tried this, but it doesn't work. Can anyone help?
awk -F, 'BEGIN{IGNORECASE = 1};NR==FNR{remove[$1]++;next}!($1 in remove)' remove.txt old.csv > new.csv
With grep:
grep -v -i -f remove.txt all.csv
Here,
-f - Obtain patterns from FILE, one per line.
-i - Ignore case
-v - Invert the matching
With awk:
awk -F, 'BEGIN{IGNORECASE=1} NR==FNR{a[$1]++;next} {for(var in a){if($3 ~ var){print}}}' remove.txt all.csv
Another awk:
awk -F, 'NR==FNR{a[tolower($1)]++;next} !(tolower($3) in a){print}' remove.txt all.csv
In your case, it won't work. Because,
IGNORECASE=1
will work only on if (x ~ /ab/) and not with array indexes.
index in array
IGNORECASE is gawk-specific, you may not be using gawk.
You're testing the wrong field.
Incrementing the array element does nothing useful.
Try this:
awk -F, 'NR==FNR{remove[tolower($1)];next}!(tolower($3) in remove)' remove.txt old.csv > new.csv

Find Values in CSV that only Appear Once

I have a csv file with thousands of lines in it. I'd like to be able to find values that only appear once in this file.
For instance
dog
dog
cat
dog
bird
I'd like to get as my result:
cat
bird
I tried using the following awk command but it returned one of each value in the file:
awk -F"," '{print $1}' test.csv|sort|uniq
Returns:
dog
cat
bird
Thank you for your help!
Just with awk:
awk -F, '{count[$1]++} END {for (key in count) if (count[key] == 1) print key}' test.csv
Close. Try:
awk -F"," '{print $1}' test.csv |sort | uniq -c | awk '{if ($1 == 1) print $2}'
the -c flag on uniq will give you counts. Next awk will look for any items with the count of 1 (first field) and print the value of the second field ($2)
Only caveat is that this will return bird before cat due to it being previously sroted. you could pipe once more to sort -r to reverse the sort direction. This would be identical to the expected answer you asked for, but it is not the original sort order.
Cutting to first field, then sorting and displaying only uniques:
cut -d ',' -f 1 test.csv | sort | uniq -u
That is, if you append -u to your command, it'd work. This is just using cut instead of awk.
If Perl is an option, this code is similar to #glenn jackman's:
perl -F, -lane '$c{$F[0]}++; END{for $k (sort keys %c){print $k if $c{$k} == 1}}' test.csv
These command-line options are used:
-n loop around each line of the input file
-l removes newlines before processing, and adds them back in afterwards
-a autosplit mode – split input lines into the #F array. Defaults to splitting on whitespace.
-e execute the perl code
-F autosplit modifier, in this case splits on ,
#F is the array of words in each line, indexed starting with $F[0]

Parsing csv using conditional statement in awk

I have a csv file
file.csv
C75ADANXX,5,20,,AGGCAGAA,AGAGTAGA,,,,,AB
C75ADANXX,5,21,,AGGCAGAA,GTAAGGAG,,,,,AB
C75ADANXX,5,22,,AGGCAGAA,ACTGCATA,,,,,AB
C75ADANXX,5,23,,AGGCAGAA,AAGGAGTA,,,,,TC
C75ADANXX,5,24,,AGGCAGAA,CTAAGCCT,,,,,TC
C75ADANXX,5,25,,TCCTGAGC,GCGTAAGA,,,,,TC
when I run the following awk command :
awk -F "," '{print$11}' file.csv ##prints last cloumn
i want to extract lines with TC ; but the following command prints nothing
awk -F "," '{if($11==TC){print$0}}' file.csv
Where am I going wrong in writing the command ? Thank you.
modified the command to
awk -F "," '{if($11=="TC\r"){print$0}}' file.csv
this file was copied from windows , it had a carriage return character at the end of the line which was obviously not seen when you print only last column.
Modify
awk -F "," '{if($11==TC){print$0}}' file.csv
To
awk -F "," '{if($11=="TC"){print$0}}' file.csv
OR even simple
awk -F, '$11=="TC"' file.csv
if($11==TC) Since variable TC is not defined before (because no quotes used, awk treats TC as variable not as string), it evaluates false always, so it prints nothing.
try this one
grep ",TC$" file.csv

Awk a range of numbers from a specific column in a csv file

I am trying to print the rows from a csv file that have a third column value greater than -39. I have tried using awk but have not been able to get the command to work:
awk -F "," '{$3 > -39}' momenttensors.csv
You have your comparison inside an action block. You want it in the pattern section. Remove the { and }.
awk -F, '$3 > -39' momenttensors.csv
Try this:
awk -F, '$3 > -39' momenttensors.csv
You need the test part. {} this is an action part.

parse a csv file that contains commans in the fields with awk

i have to use awk to print out 4 different columns in a csv file. The problem is the strings are in a $x,xxx.xx format. When I run the regular awk command.
awk -F, {print $1} testfile.csv
my output `ends up looking like
307.00
$132.34
30.23
What am I doing wrong.
"$141,818.88","$52,831,578.53","$52,788,069.53"
this is roughly the input. The file I have to parse is 90,000 rows and about 40 columns
This is how the input is laid out or at least the parts of it that I have to deal with. Sorry if I made you think this wasn't what I was talking about.
If the input is "$307.00","$132.34","$30.23"
I want the output to be in a
$307.00
$132.34
$30.23
Oddly enough I had to tackle this problem some time ago and I kept the code around to do it. You almost had it, but you need to get a bit tricky with your field separator(s).
awk -F'","|^"|"$' '{print $2}' testfile.csv
Input
# cat testfile.csv
"$141,818.88","$52,831,578.53","$52,788,069.53"
"$2,558.20","$482,619.11","$9,687,142.69"
"$786.48","$8,568,159.41","$159,180,818.00"
Output
# awk -F'","|^"|"$' '{print $2}' testfile.csv
$141,818.88
$2,558.20
$786.48
You'll note that the "first" field is actually $2 because of the field separator ^". Small price to pay for a short 1-liner if you ask me.
I think what you're saying is that you want to split the input into CSV fields while not getting tripped up by the commas inside the double quotes. If so...
First, use "," as the field separator, like this:
awk -F'","' '{print $1}'
But then you'll still end up with a stray double-quote at the beginning of $1 (and at the end of the last field). Handle that by stripping quotes out with gsub, like this:
awk -F'","' '{x=$1; gsub("\"","",x); print x}'
Result:
echo '"abc,def","ghi,xyz"' | awk -F'","' '{x=$1; gsub("\"","",x); print x}'
abc,def
In order to let awk handle quoted fields that contain the field separator, you can use a small script I wrote called csvquote. It temporarily replaces the offending commas with nonprinting characters, and then you restore them at the end of your pipeline. Like this:
csvquote testfile.csv | awk -F, {print $1} | csvquote -u
This would also work with any other UNIX text processing program like cut:
csvquote testfile.csv | cut -d, -f1 | csvquote -u
You can get the csvquote code here: https://github.com/dbro/csvquote
The data file:
$ cat data.txt
"$307.00","$132.34","$30.23"
The AWK script:
$ cat csv.awk
BEGIN { RS = "," }
{ gsub("\"", "", $1);
print $1 }
The execution:
$ awk -f csv.awk data.txt
$307.00
$132.34
$30.23