Related
I have the following list of strings in shell script:
something-7-5-2020.dump
another-7-5-2020.dump
anoter2-6-5-2020.dump
another-4-5-2020.dump
another2-4-5-2020.dump
something-2-5-2020.dump
another-2-5-2020.dump
8-1-2021
26-1-2021
20-1-2021
19-1-2021
3-9-2020
29-9-2020
28-9-2020
24-9-2020
1-9-2020
6-8-2020
20-8-2020
18-8-2020
12-8-2020
10-8-2020
7-7-2020
5-7-2020
27-7-2020
7-6-2020
5-6-2020
23-6-2020
18-6-2020
28-5-2020
26-5-2020
9-12-2020
28-12-2020
15-12-2020
1-12-2020
27-11-2020
20-11-2020
19-11-2020
18-11-2020
1-11-2020
11-11-2020
31-10-2020
29-10-2020
27-10-2020
23-10-2020
21-10-2020
15-10-2020
23-09-2020
So my goal is to sort them by date, but it's in dd-mm-yyyy and d-m-yyyy format and sometimes there's a word before like word-dd-mm-yyyy. I would like to create a function to sort the values like any other language so it ignores the first word, casts the date to a common format and compares that format. In javascript it would be something like:
arrayOfStrings.sort((a, b) => functionToOrderStrings())
My code to obtain the array is the following:
dumps=$(gsutil ls gs://organization-dumps/ambient | sed "s:gs\://organization-dumps/ambient/::" | sed '/^$/d' | sed 's:/$::' | sort --reverse --key=3 --key=2 --key=1 --field-separator=-)
echo "$dumps"
I would like to say that I've already searched this in Stackoverflow and none of the answers did help me, because all of them are oriented to sort dates in correct format and that's not my case.
If you have the results in a pipeline, involving an array seems completely superfluous here.
You can apply a technique called a Schwartzian transform: add a prefix to each line with a normalized version the data so it can be easily sorted, then sort, then discard the prefix.
I'm guessing something like the following;
gsutil ls gs://organization-dumps/ambient |
awk '{ sub("gs:\/\/organization-dumps/ambient/", "");
if (! $0) next;
sub("/$", "");
d = $0;
sub(/^[^0-9][^-]*-/, "", d);
sub(/[^0-9]*$/, "", d);
split(d, w, "-");
printf "%04i-%02i-%02i\t%s\n", w[3], w[2], w[1], $0 }' |
sort -n | cut -f2-
In so many words, we are adding a tab-delimited field in front of every line, then sorting on that, then discarding the first field with cut -f2-. The field extraction contains some assumptions which seem to be valid for your test data, but may need additional tweaking if you have real data with corner cases like if the label before the date could sometimes contain a number with dashes around it, too.
If you want to capture the result in a variable, like in your original code, that's easy to do; but usually, you should just run everything in a pipeline.
Notice that I factored your multiple sed scripts into the Awk script, too, some of that with a fair amount of guessing as to what the input looks like and what the sed scripts were supposed to accomplish. (Perhaps also note that sed, like Awk, is a scripting language; to run several sed commands on the same input, just put them after each other in the same sed script.)
Preprocess input to be in the format you want it to be for sorting.
Sort
Remove artifacts from step 1
The following:
sed -E '
# extract the date and put it in first column separated by tab
# this could be better, its just an example
s/(.*-)?([0-9]?[0-9]-[0-9]?[0-9]-[0-9]{4})/\2\t&/;
# If day is a single digit, add a zero in front
s/^([0-9]-)/0\1/;
# If month is a single digit, add a zero in front
s/^([0-9][0-9]-)([0-9]-)/\10\2/
# year in front? no idea - shuffle the way you want
s/([0-9]{2})-([0-9]{2})-([0-9]{4})/\3-\2-\1/
' input.txt | sort | cut -f2-
outputs:
another-2-5-2020.dump
something-2-5-2020.dump
another-4-5-2020.dump
another2-4-5-2020.dump
anoter2-6-5-2020.dump
another-7-5-2020.dump
something-7-5-2020.dump
26-5-2020
28-5-2020
5-6-2020
7-6-2020
18-6-2020
23-6-2020
5-7-2020
7-7-2020
27-7-2020
6-8-2020
10-8-2020
12-8-2020
18-8-2020
20-8-2020
1-9-2020
3-9-2020
23-09-2020
24-9-2020
28-9-2020
29-9-2020
15-10-2020
21-10-2020
23-10-2020
27-10-2020
29-10-2020
31-10-2020
1-11-2020
11-11-2020
18-11-2020
19-11-2020
20-11-2020
27-11-2020
1-12-2020
9-12-2020
15-12-2020
28-12-2020
8-1-2021
19-1-2021
20-1-2021
26-1-2021
Using GNU awk:
gsutil ls gs://organization-dumps/ambient | awk '{ match($0,/[[:digit:]]{1,2}-[[:digit:]]{1,2}-[[:digit:]]{4}/);dayt=substr($0,RSTART,RLENGTH);split(dayt,map,"-");length(map[1])==1?map[1]="0"map[1]:map[1]=map[1];length(map[2])==1?map[2]="0"map[2]:map[2]=map[2];map1[mktime(map[3]" "map[2]" "map[1]" 00 00 00")]=$0 } END { PROCINFO["sorted_in"]="#ind_num_asc";for (i in map1) { print map1[i] } }'
Explanation:
gsutil ls gs://organization-dumps/ambient | awk '{
match($0,/[[:digit:]]{1,2}-[[:digit:]]{1,2}-[[:digit:]]{4}/); # Check that lines contain a date
dayt=substr($0,RSTART,RLENGTH); # Extract the date
split(dayt,map,"-"); # Split the date in the array map based on "-" as the delimiter
length(map[1])==1? map[1]="0"map[1]:map[1]=map[1];length(map[2])==1?map[2]="0"map[2]:map[2]=map[2]; # Pad the month and day with "0" if required
map1[mktime(map[3]" "map[2]" "map[1]" 00 00 00")]=$0 # Get the epoch format date based on the values in the map array and use this for the index of the array map1 with the line as the value
}
END {
PROCINFO["sorted_in"]="#ind_num_asc"; # Set the ordering of the array
for (i in map1) {
print map1[i] # Loop through map1 and print the values (lines)
}
}'
Using GNU awk, you can do this fairly easy:
awk 'BEGIN{PROCINFO["sorted_in"]="#ind_num_asc"; FS="."}
{n=split($1,t,"-"); a[t[n]*10000 + t[n-1]*100 + t[n-2]]=$0}
END {for(i in a) print a[i]}' file
Essentially, we are asking GNU awk to traverse an array by index in ascending numeric order. Per line read, we extract the date. The date is always located before the <dot>-character and thus always in field 1 if the dot is the field separator (FS="."). We split the first field by the hyphen and use the total number of fields to extract the date. We convert the date simplistically to some number (YYYY*10000+MM*100+DD; DD<100 && MM*100 < 10000) and ask awk to sort it by that number.
It is now possible to combine the full pipe-line in a single awk:
$ gsutil ls gs://organization-dumps/ambient \
| awk 'BEGIN{PROCINFO["sorted_in"]="#ind_num_asc"; FS="."}
{sub("gs://organization-dumps/ambient/",""); sub("/$","")}
(NF==0){next}
{n=split($1,t,"-"); a[t[n]*10000 + t[n-1]*100 + t[n-2]]=$0}
END {for(i in a) print a[i]}'
I have a large log file, from which I need to extract some specific data, to be more precise, the values of distinct fields that appear repeatedly, i.e. I need to get some information from many CDRs, such as call type, origination number, etc.
The original text formatting is as per below:
Reason Code:"XXX", Result Code:XXX, Desc: "XXX"
..
A_NUMBER.ADDRESS = XXX
..
Using egrep I have managed to get the required lines, which appear to be like:
Reason Code:"XXX", Result Code:XXX, Desc: "XXX"
RECORD_IDENTIFICATION.FILE_ID: XXX
A_NUMBER.ADDRESS = XXX
Call is from XXXX, VDATE=XXXX.
but I am not being able to format them in a tabular style, grouped by Reason, File_ID, A_Num and Call Date, acting as column heads,
like
Reason Code | File_ID | A_Number | Date
xxxx | xxxx | xxxx | xxxx |
I am not really interested in the appearance, I just want the elements to be consecutive, in order to belong to the same call.
I have messed with different variants of awk, sed and printf, but nothing seems to work.
I have tried to put the total characters value as a parameter in printf
printf "%-205s\n" $(grep -E 'Reason Code|RECORD_IDENTIFICATION.FILE_ID|A_NUMBER.ADDRESS|Call is from' file.err)
or
printf "%-65s | %-65s | %-65s | %-65s" $(grep -E 'Reason Code|RECORD_IDENTIFICATION.FILE_ID|A_NUMBER.ADDRESS' file.err | awk 'FS = "\n" {print $1}')
but the values in output are scrambled and unusable.
In my opinion the solution may lay in some sort of loop, which awk seems to support, but I am not being able to sort it out.
Any help would be very appreciated.
Thank You
You can transform the output of your grep command with sed :
sed 'N;N;N;s/Reason Code:"\([^"]*\).*FILE_ID: \([^\n]*\).*A_NUMBER.ADDRESS = \([^\n]*\).*VDATE=\([^.]*\).*/\1 \2 \3 \4/'
$ echo ''' Reason Code:"XXX", Result Code:XXX, Desc: "XXX"
RECORD_IDENTIFICATION.FILE_ID: XXX
A_NUMBER.ADDRESS = XXX
Call is from XXXX, VDATE=XXXX.''' | sed 'N;N;N;s/Reason Code:"\([^"]*\).*FILE_ID: \([^\n]*\).*A_NUMBER.ADDRESS = \([^\n]*\).*VDATE=\([^.]*\).*/\1 \2 \3 \4/'
XXX XXX XXX XXXX
However, it would be best to avoid using grep and let sed also do the filtering. I can't propose such a solution since you didn't post the format of your unfiltered data.
I have 2 files refer.txt and parse.txt
refer.txt contains the following
julie,remo,rob,whitney,james
parse.txt contains
remo/hello/1.0,remo/hello2/2.0,remo/hello3/3.0,whitney/hello/1.0,julie/hello/2.0,julie/hello/3.0,rob/hello/4.0,james/hello/6.0
Now my output.txt should list the files in parse.txt based on the order specified in refer.txt
ex of output.txt should be:
julie/hello/2.0,julie/hello/3.0,remo/hello/1.0,remo/hello2/2.0,remo/hello3/3.0,rob/hello/4.0,whitney/hello/1.0,james/hello/6.0
i have tried the following code:
sort -nru refer.txt parse.txt
but no luck.
please assist me.TIA
You can do that using gnu-awk:
awk -F/ -v RS=',|\n' 'FNR==NR{a[$1] = (a[$1])? a[$1] "," $0 : $0 ; next}
{s = (s)? s "," a[$1] : a[$1]} END{print s}' parse.txt refer.txt
Output:
julie/hello/2.0,julie/hello/3.0,remo/hello/1.0,remo/hello2/2.0,remo/hello3/3.0,rob/hello/4.0,whitney/hello/1.0,james/hello/6.0
Explanation:
-F/ # Use field separator as /
-v RS=',|\n' # Use record separator as comma or newline
NR == FNR { # While processing parse.txt
a[$1]=(a[$1])?a[$1] ","$0:$0 # create an array with 1st field as key and value as all the
# records with keys julie, remo, rob etc.
}
{ # while processing the second file refer.txt
s = (s)?s "," a[$1]:a[$1] # aggregate all values by reading key from 2nd file
}
END {print s } # print all the values
In pure native bash (4.x):
# read each file into an array
IFS=, read -r -a values <parse.txt
IFS=, read -r -a ordering <refer.txt
# create a map from content before "/" to comma-separated full values in preserved order
declare -A kv=( )
for value in "${values[#]}"; do
key=${value%%/*}
if [[ ${kv[$key]} ]]; then
kv[$key]+=",$value" # already exists, comma-separate
else
kv[$key]="$value"
fi
done
# go through refer list, putting full value into "out" array for each entry
out=( )
for value in "${ordering[#]}"; do
out+=( "${kv[$value]}" )
done
# print "out" array in comma-separated form
IFS=,
printf '%s\n' "${out[*]}" >output.txt
If you're getting more output fields than you have input fields, you're probably trying to run this with bash 3.x. Since associative array support is mandatory for correct operation, this won't work.
tr , "\n" refer.txt | cat -n >person_id.txt # 'cut -n' not posix, use sed and paste
cat person_id.txt | while read person_id person_key
do
print "$person_id" > $person_key
done
tr , "\n" parse.txt | sed 's/(^[^\/]*)(\/.*)$/\1 \1\2/' >person_data.txt
cat person_data.txt | while read foreign_key person_data
do
person_id="$(<$foreign_key)"
print "$person_id" " " "$person_data" >>merge.txt
done
sort merge.txt >output.txt
A text book data processing approach, a person id table, a person data table, merged on a common key field, which is the first name of the person:
[person_key] [person_id]
- person id table, a unique sortable 'id' for each person (line number in this instance, since that is the desired sort order), and key for each person (their first name)
[person_key] [person_data]
- person data table, the data for each person indexed by 'person_key'
[person_id] [person_data]
- a merge of the 'person_id' table and 'person_data' table on 'person_key', which can then be sorted on person_id, giving the output as requested
The trick is to implement an associative array using files, the file name being the key (in this instance 'person_key'), the content being the value. [Essentially a random access file implemented using the filesystem.]
This actually adds a step to the otherwise simple but not very efficient task of grepping parse.txt with each value in refer.txt - which is more efficient I'm not sure.
NB: The above code is very unlikely to work out of the box.
NBB: On reflection, probably a better way of doing this would be to use the file system to create a random access file of parse.txt (essentially an index), and to then consider refer.txt as a batch file, submitting it as a job as such, printing out from the parse.txt random access file the data for each of the names read in from refer.txt in turn:
# 1) index data file on required field
cat person_data.txt | while read data
do
key="$(print "$data" | sed 's/(^[^\/]*)/\1/')" # alt. `cut -d'/' -f1` ??
print "$data" >>./person_data/"$key"
done
# 2) run batch job
cat refer_data.txt | while read key
do
print ./person_data/"$key"
done
However having said that, using egrep is probably just as rigorous a solution or at least for small datasets, I would most certainly use this approach given the specific question posed. (Or maybe not! The above could well prove faster as well as being more robust.)
Command
while read line; do
grep -w "^$line" <(tr , "\n" < parse.txt)
done < <(tr , "\n" < refer.txt) | paste -s -d , -
Key points
For both files, newlines are translated to commas using the tr command (without actually changing the files themselves). This is useful because while read and grep work under the assumption that your records are separated by newlines instead of commas.
while read will read in every name from refer.txt, (i.e julie, remo, etc.) and then use grep to retrieve lines from parse.txt containing that name.
The ^ in the regex ensures matching is only performed from the start of the string and not in the middle (thanks to #CharlesDuffy's comment below), and the -w option for grep allows whole-word matching only. For example, this ensures that "rob" only matches "rob/..." and not "robby/..." or "throb/...".
The paste command at the end will comma-separate the results. Removing this command will print each result on its own line.
If I have a csv file, is there a quick bash way to print out the contents of only any single column? It is safe to assume that each row has the same number of columns, but each column's content would have different length.
You could use awk for this. Change '$2' to the nth column you want.
awk -F "\"*,\"*" '{print $2}' textfile.csv
yes. cat mycsv.csv | cut -d ',' -f3 will print 3rd column.
The simplest way I was able to get this done was to just use csvtool. I had other use cases as well to use csvtool and it can handle the quotes or delimiters appropriately if they appear within the column data itself.
csvtool format '%(2)\n' input.csv
Replacing 2 with the column number will effectively extract the column data you are looking for.
Landed here looking to extract from a tab separated file. Thought I would add.
cat textfile.tsv | cut -f2 -s
Where -f2 extracts the 2, non-zero indexed column, or the second column.
Here is a csv file example with 2 columns
myTooth.csv
Date,Tooth
2017-01-25,wisdom
2017-02-19,canine
2017-02-24,canine
2017-02-28,wisdom
To get the first column, use:
cut -d, -f1 myTooth.csv
f stands for Field and d stands for delimiter
Running the above command will produce the following output.
Output
Date
2017-01-25
2017-02-19
2017-02-24
2017-02-28
To get the 2nd column only:
cut -d, -f2 myTooth.csv
And here is the output
Output
Tooth
wisdom
canine
canine
wisdom
incisor
Another use case:
Your csv input file contains 10 columns and you want columns 2 through 5 and columns 8, using comma as the separator".
cut uses -f (meaning "fields") to specify columns and -d (meaning "delimiter") to specify the separator. You need to specify the latter because some files may use spaces, tabs, or colons to separate columns.
cut -f 2-5,8 -d , myvalues.csv
cut is a command utility and here is some more examples:
SYNOPSIS
cut -b list [-n] [file ...]
cut -c list [file ...]
cut -f list [-d delim] [-s] [file ...]
I think the easiest is using csvkit:
Gets the 2nd column:
csvcut -c 2 file.csv
However, there's also csvtool, and probably a number of other csv bash tools out there:
sudo apt-get install csvtool (for Debian-based systems)
This would return a column with the first row having 'ID' in it.
csvtool namedcol ID csv_file.csv
This would return the fourth row:
csvtool col 4 csv_file.csv
If you want to drop the header row:
csvtool col 4 csv_file.csv | sed '1d'
First we'll create a basic CSV
[dumb#one pts]$ cat > file
a,b,c,d,e,f,g,h,i,k
1,2,3,4,5,6,7,8,9,10
a,b,c,d,e,f,g,h,i,k
1,2,3,4,5,6,7,8,9,10
Then we get the 1st column
[dumb#one pts]$ awk -F , '{print $1}' file
a
1
a
1
Many answers for this questions are great and some have even looked into the corner cases.
I would like to add a simple answer that can be of daily use... where you mostly get into those corner cases (like having escaped commas or commas in quotes etc.,).
FS (Field Separator) is the variable whose value is dafaulted to
space. So awk by default splits at space for any line.
So using BEGIN (Execute before taking input) we can set this field to anything we want...
awk 'BEGIN {FS = ","}; {print $3}'
The above code will print the 3rd column in a csv file.
The other answers work well, but since you asked for a solution using just the bash shell, you can do this:
AirBoxOmega:~ d$ cat > file #First we'll create a basic CSV
a,b,c,d,e,f,g,h,i,k
1,2,3,4,5,6,7,8,9,10
a,b,c,d,e,f,g,h,i,k
1,2,3,4,5,6,7,8,9,10
a,b,c,d,e,f,g,h,i,k
1,2,3,4,5,6,7,8,9,10
a,b,c,d,e,f,g,h,i,k
1,2,3,4,5,6,7,8,9,10
a,b,c,d,e,f,g,h,i,k
1,2,3,4,5,6,7,8,9,10
a,b,c,d,e,f,g,h,i,k
1,2,3,4,5,6,7,8,9,10
And then you can pull out columns (the first in this example) like so:
AirBoxOmega:~ d$ while IFS=, read -a csv_line;do echo "${csv_line[0]}";done < file
a
1
a
1
a
1
a
1
a
1
a
1
So there's a couple of things going on here:
while IFS=, - this is saying to use a comma as the IFS (Internal Field Separator), which is what the shell uses to know what separates fields (blocks of text). So saying IFS=, is like saying "a,b" is the same as "a b" would be if the IFS=" " (which is what it is by default.)
read -a csv_line; - this is saying read in each line, one at a time and create an array where each element is called "csv_line" and send that to the "do" section of our while loop
do echo "${csv_line[0]}";done < file - now we're in the "do" phase, and we're saying echo the 0th element of the array "csv_line". This action is repeated on every line of the file. The < file part is just telling the while loop where to read from. NOTE: remember, in bash, arrays are 0 indexed, so the first column is the 0th element.
So there you have it, pulling out a column from a CSV in the shell. The other solutions are probably more practical, but this one is pure bash.
You could use GNU Awk, see this article of the user guide.
As an improvement to the solution presented in the article (in June 2015), the following gawk command allows double quotes inside double quoted fields; a double quote is marked by two consecutive double quotes ("") there. Furthermore, this allows empty fields, but even this can not handle multiline fields. The following example prints the 3rd column (via c=3) of textfile.csv:
#!/bin/bash
gawk -- '
BEGIN{
FPAT="([^,\"]*)|(\"((\"\")*[^\"]*)*\")"
}
{
if (substr($c, 1, 1) == "\"") {
$c = substr($c, 2, length($c) - 2) # Get the text within the two quotes
gsub("\"\"", "\"", $c) # Normalize double quotes
}
print $c
}
' c=3 < <(dos2unix <textfile.csv)
Note the use of dos2unix to convert possible DOS style line breaks (CRLF i.e. "\r\n") and UTF-16 encoding (with byte order mark) to "\n" and UTF-8 (without byte order mark), respectively. Standard CSV files use CRLF as line break, see Wikipedia.
If the input may contain multiline fields, you can use the following script. Note the use of special string for separating records in output (since the default separator newline could occur within a record). Again, the following example prints the 3rd column (via c=3) of textfile.csv:
#!/bin/bash
gawk -- '
BEGIN{
RS="\0" # Read the whole input file as one record;
# assume there is no null character in input.
FS="" # Suppose this setting eases internal splitting work.
ORS="\n####\n" # Use a special output separator to show borders of a record.
}
{
nof=patsplit($0, a, /([^,"\n]*)|("(("")*[^"]*)*")/, seps)
field=0;
for (i=1; i<=nof; i++){
field++
if (field==c) {
if (substr(a[i], 1, 1) == "\"") {
a[i] = substr(a[i], 2, length(a[i]) - 2) # Get the text within
# the two quotes.
gsub(/""/, "\"", a[i]) # Normalize double quotes.
}
print a[i]
}
if (seps[i]!=",") field=0
}
}
' c=3 < <(dos2unix <textfile.csv)
There is another approach to the problem. csvquote can output contents of a CSV file modified so that special characters within field are transformed so that usual Unix text processing tools can be used to select certain column. For example the following code outputs the third column:
csvquote textfile.csv | cut -d ',' -f 3 | csvquote -u
csvquote can be used to process arbitrary large files.
I needed proper CSV parsing, not cut / awk and prayer. I'm trying this on a mac without csvtool, but macs do come with ruby, so you can do:
echo "require 'csv'; CSV.read('new.csv').each {|data| puts data[34]}" | ruby
I wonder why none of the answers so far have mentioned csvkit.
csvkit is a suite of command-line tools for converting to and working
with CSV
csvkit documentation
I use it exclusively for csv data management and so far I have not found a problem that I could not solve using cvskit.
To extract one or more columns from a cvs file you can use the csvcut utility that is part of the toolbox. To extract the second column use this command:
csvcut -c 2 filename_in.csv > filename_out.csv
csvcut reference page
If the strings in the csv are quoted, add the quote character with the q option:
csvcut -q '"' -c 2 filename_in.csv > filename_out.csv
Install with pip install csvkit or sudo apt install csvkit.
Simple solution using awk. Instead of "colNum" put the number of column you need to print.
cat fileName.csv | awk -F ";" '{ print $colNum }'
csvtool col 2 file.csv
where 2 is the column you are interested in
you can also do
csvtool col 1,2 file.csv
to do multiple columns
You can't do it without a full CSV parser.
If you know your data will not be quoted, then any solution that splits on , will work well (I tend to reach for cut -d, -f1 | sed 1d), as will any of the CSV manipulation tools.
If you want to produce another CSV file, then xsv, csvkit, csvtool, or other CSV manipulation tools are appropriate.
If you want to extract the contents of one single column of a CSV file, unquoting them so that they can be processed by subsequent commands, this Python 1-liner does the trick for CSV files with headers:
python -c 'import csv,sys'$'\n''for row in csv.DictReader(sys.stdin): print(row["message"])'
The "message" inside of the print function selects the column.
If the CSV file doesn't have headers:
python -c 'import csv,sys'$'\n''for row in csv.reader(sys.stdin): print(row[1])'
Python's CSV library supports all kinds of CSV dialects, so if your CSV file uses different conventions, it's possible to support them with relatively little change to the code.
Been using this code for a while, it is not "quick" unless you count "cutting and pasting from stackoverflow".
It uses ${##} and ${%%} operators in a loop instead of IFS. It calls 'err' and 'die', and supports only comma, dash, and pipe as SEP chars (that's all I needed).
err() { echo "${0##*/}: Error:" "$#" >&2; }
die() { err "$#"; exit 1; }
# Return Nth field in a csv string, fields numbered starting with 1
csv_fldN() { fldN , "$1" "$2"; }
# Return Nth field in string of fields separated
# by SEP, fields numbered starting with 1
fldN() {
local me="fldN: "
local sep="$1"
local fldnum="$2"
local vals="$3"
case "$sep" in
-|,|\|) ;;
*) die "$me: arg1 sep: unsupported separator '$sep'" ;;
esac
case "$fldnum" in
[0-9]*) [ "$fldnum" -gt 0 ] || { err "$me: arg2 fldnum=$fldnum must be number greater or equal to 0."; return 1; } ;;
*) { err "$me: arg2 fldnum=$fldnum must be number"; return 1;} ;;
esac
[ -z "$vals" ] && err "$me: missing arg2 vals: list of '$sep' separated values" && return 1
fldnum=$(($fldnum - 1))
while [ $fldnum -gt 0 ] ; do
vals="${vals#*$sep}"
fldnum=$(($fldnum - 1))
done
echo ${vals%%$sep*}
}
Example:
$ CSVLINE="example,fields with whitespace,field3"
$ $ for fno in $(seq 3); do echo field$fno: $(csv_fldN $fno "$CSVLINE"); done
field1: example
field2: fields with whitespace
field3: field3
You can also use while loop
IFS=,
while read name val; do
echo "............................"
echo Name: "$name"
done<itemlst.csv
I'm trying to write a script that looks at a part of a line, does a sort -u or something to look for unique occurrences, and then displays the output, sorted by the ORIGINAL ordering of the lines. In other words, only the FIRST occurrence of that part of the line would show up.
I managed to do it using cut, but my output just displays the cut portion of the data. How could I do it so that it gets the entire line?
Here's what I've got so far:
cut -d, -f6 infile.txt | cut -c4-11 | grep -n . | sort -t: -k2,2 -u | sort -t: -k1n,1 | cut -d: -f2-
I know the data doesn't have an extra : or a , in a place that would break this script. But this only outputs the data that was unique. How can I get the entire line? I would prefer to stay away from perl, but awk is okay (though I don't know it very well).
Sample:
If the input file is this (note, the ABCDEFGH is not real, I just put it there to illustrate what I mean):
A....,....,...........,.....,....,...20130718......,.........,...........,......
B....,....,...........,.....,....,...20130714......,.........,...........,......
C....,....,...........,.....,....,...20130718......,.........,...........,......
D....,....,...........,.....,....,...20130719......,.........,...........,......
E....,....,...........,.....,....,...20130713......,.........,...........,......
F....,....,...........,.....,....,...20130714......,.........,...........,......
G....,....,...........,.....,....,...20130630......,.........,...........,......
H....,....,...........,.....,....,...20130718......,.........,...........,......
My program outputs:
20130718
20130714
20130719
20130713
20130630
I want to see:
A....,....,...........,.....,....,...20130718......,.........,...........,......
B....,....,...........,.....,....,...20130714......,.........,...........,......
D....,....,...........,.....,....,...20130719......,.........,...........,......
E....,....,...........,.....,....,...20130713......,.........,...........,......
G....,....,...........,.....,....,...20130630......,.........,...........,......
Yes, awk is your best bet. Here's a mysterious example:
awk -F, '!seen[substr($6,4,8)]++' infile.txt
Explanation:
options:
-F, set the field separator to ,
condition:
substr($6,4,8) up to 8 characters starting at the fourth character
of the sixth field
seen[...]++ seen is an associative array (dictionary). Increment the
value associated with ..., and return the old value
!seen[...]++ if there was no old value, perform the action
action:
There is no action, only a condition, so the default action is
performed if the test succeeds. The default action is to print
the line. So the line will be printed if the relevant characters of
the sixth field haven't yet been seen.
Test:
$ awk -F, '!seen[substr($6,4,8)]++' <<EOF
> A....,....,...........,.....,....,...20130718......,.........,...........,......
> B....,....,...........,.....,....,...20130714......,.........,...........,......
> C....,....,...........,.....,....,...20130718......,.........,...........,......
> D....,....,...........,.....,....,...20130719......,.........,...........,......
> E....,....,...........,.....,....,...20130713......,.........,...........,......
> F....,....,...........,.....,....,...20130714......,.........,...........,......
> G....,....,...........,.....,....,...20130630......,.........,...........,......
> H....,....,...........,.....,....,...20130718......,.........,...........,......
> EOF
A....,....,...........,.....,....,...20130718......,.........,...........,......
B....,....,...........,.....,....,...20130714......,.........,...........,......
D....,....,...........,.....,....,...20130719......,.........,...........,......
E....,....,...........,.....,....,...20130713......,.........,...........,......
G....,....,...........,.....,....,...20130630......,.........,...........,......
$