while loop bash script

Question

i have a text file contains following information:

/media/Arc/eo_archive_test/MODIS/L2_LAC_OC/A2006001071000.L2_LAC_OC.x.hdf:2006:365
/media/Arc/eo_archive_test/MODIS/L2_LAC_OC/A2006001084000.L2_LAC_OC.x.hdf:2013:011
/media/Arc/eo_archive_test/MODIS/L2_LAC_OC/A2006001084500.L2_LAC_OC.x.hdf:2005:365
....

I want to echo $f1 where $f2 is "2013" and $f3 is "011". i am using following script but its echoing all. what am i doing wrong here?

file=/media/Arc/eo_archive_test/MODIS/input/all_file_list.txt
while IFS=: read -r f1 f2 f3
do
    [ "$f2" = "2013" ] || [ "$f3" = "011" ]
    echo $f1
done < "$file"

any solution? Thank you in advance

glenn jackman · Accepted Answer · 2014-03-06 15:52:03Z

2

You need to connect the test to the action

[[ $f2 == 2013 && $f3 == 011 ]] && echo $f1

or

if [ "$f2" = "2013" ] && [ "$f3" = "011" ]; then
    echo $f1
fi

What you are doing now is performing the test commands and ignoring the exit status. So the echo command does indeed execute for every line.

answered Mar 6, 2014 at 15:52

glenn jackman

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Comments

Birei · Accepted Answer · 2014-03-06 15:51:42Z

1

You have to include the comparison inside an if sentence and use && instead of ||, like:

file=/media/Arc/eo_archive_test/MODIS/input/all_file_list.txt
while IFS=: read -r f1 f2 f3
do
    if [ "$f2" = "2013" ] && [ "$f3" = "011" ]; then
        echo $f1
    fi
done < "$file"

answered Mar 6, 2014 at 15:51

Birei

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5 Comments

neel Over a year ago

thank you very much.this solution works; i am very happy about that. I am greedy ;). now I am little bit more ambitious.. what if, I want to add ... "$f3 = 001 to 007". what would be the correct syntax for that?? thank you in advance....

Birei Over a year ago

@neel: Use -gt and -lt to compare numbers, like:[ "$f3" -gt "000" ] && [ "$f3" -lt "008" ]

neel Over a year ago

Grate, Awesome....Thank you very mush for the effort; i really appreciate it but u know, nothing is enough for me. :). ######### ok, now the next help I need is: in my "$f2" column I have data ranged from "2006" to "2013" (year) and in "$f3" column, from "000" to "365" (day of year). I need to find a efficient looping method which will echo "$f1" based on year wise weekly condition in different text file name like 2006_01.txt, 2006_52, 2007_03.txt, 2007_52.txt and so...... any help, I might get?

neel Over a year ago

... i was able to automate part of my need but still i have to find out how i can deal the weeks.. I Have put my code in the comment section, bellow

Birei Over a year ago

@neel: That can be considered a different question. You should better create a new one for it.

twalberg · Accepted Answer · 2014-03-06 16:12:37Z

1

You are echo-ing $f1 always, regardless of whether the line matched. Try this instead:

[[ "${f2}" == "2013" ]] && [[ "${f3}" == "011" ]] && echo "${f1}"

answered Mar 6, 2014 at 16:12

twalberg

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Comments

tripleee · Accepted Answer · 2014-03-07 05:57:35Z

0

This fits Awk's processing model hand in glove.

awk -F : '$2 == "2013" && $3 == "011" { print $1 }'  /media/Arc/eo_archive_test/MODIS/input/all_file_list.txt

If you want a regex instead, that's done like $3 ~ /^00[1-7]$/ or you could do a numeric comparison $3 > 0 && $3 <= 7.

answered Mar 7, 2014 at 5:57

tripleee

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Comments

neel · Accepted Answer · 2014-03-07 10:54:38Z

... as mentioned above, i was able to automate part of my need; a little more help required, here is the code....

file=/media/Arc/eo_archive_test/MODIS/input/all_file_list.txt
while IFS=: read -r f1 f2 f3
do
for year in "2006" "2007" "2008" "2009" "2010" "2011" "2012" "2013"
do
[[ $f2 == $year ]] 
for doy in "001" "002" "003" "004" "005" "006" "007" # here we need some automation; seeking help
do
[[ $f3 == $doy ]] && echo $f1 >> test.txt
done
done
done < "$file"

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