Substitute date for another date format

[alqsp]

Hi,

I have a file with date's in this format 30-JAN-00 that I need to convert to this format 2000-01-3000.00.00.

Any ideas on how to first search the file line by line for a month (jan-dec) and then confirm it's a date field (DD-MMM-YY) because it's possible the text JAN, FEB etc. can appear in a comments field on the file.

Cheers.

 

[mrregan]

Will the date always appear in a specific field position?

 

[Chapter11]

gnu's version of date will take your input with -d and output it however you would like.

 

[olded]

# Here's my take:
# don't even want to do anything if there's no dashes.
# assume data 30-JAN-00 like this is a field all by itself
# split the field into 3 if it has dashes
# change month to a number
# if all 3 fields are numeric change the field to new structure

# I leave the possible Y2K problem to you, and I leave it
# to you to add your time string.

#!/bin/ksh


while read line
do
if ( echo $line|grep - > /dev/null )
then
line=$(echo $line|nawk -f awkfile)
fi
echo $line >> new.file

done < data.file

# and here's awkfile:

# awkfile
{
# for each field
for(i=1; i<=NF; i++)
{
# need a dash
if ( match($i, &quot;-&quot > 0)
{
# 3 fields
anf=split($i, a, &quot;-&quot
if (anf == 3)
{
mno=month_num(a[2])
# set your field if it's numeric
if ( is_numeric(a[1]) && is_numeric(mno) && is_numeric(a[3]) )
$i=sprintf(&quot;20%s-%02d-%02d\n&quot;, a[3], mno, a[1])
}
}
}
print $0
}

function is_numeric(field) {
if ( field ~ /^[0-9]+$/ )
return 1
else
return 0
}

function month_num(month) {

if (month == &quot;JAN&quot
return 1
if (month == &quot;FEB&quot
return 2
if (month == &quot;MAR&quot
return 3
if (month == &quot;APR&quot
return 4
if (month == &quot;MAY&quot
return 5
if (month == &quot;JUN&quot
return 6
if (month == &quot;JUL&quot
return 7
if (month == &quot;AUG&quot
return 8
if (month == &quot;SEP&quot
return 9
if (month == &quot;OCT&quot
return 10
if (month == &quot;NOV&quot
return 11
if (month == &quot;DEC&quot
return 12
return &quot;E&quot;

}