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Full Discussion: Changing CSV files with date . Subtracting date by values
Top Forums UNIX for Beginners Questions & Answers Changing CSV files with date . Subtracting date by values Post 303025439 by Peasant on Friday 2nd of November 2018 11:36:57 AM
Old 11-02-2018
Fixed some typos..
I'm not sure i follow.
Input now is also inconsistent, with first two rows having 13 fields and last having 12.

Now you say you require fields 2,4 and 10, but on expected output you changed only field 4 for the first two lines and field 5 for the last line.

I have no idea what to do with 2,10, but we can work with 4 and 5 using awk match and regex.
Will it be a good guess now, or are we missing some input again ?

Code:
BEGIN {
FS=";"
mweek=52
}
#NR > 1 { # if we do not have header in our input ...
{
match($0,/P[12][0-9][0-9][0-9][0-5][0-9]/)
dw=substr($0,RSTART+1,RLENGTH-1)
year=substr(dw,1,4)
week=substr(dw,5,6)
variance=( year > 2015 ) ? 6 : 5

if ( int(week) == variance ) { week=mweek ; year=year - 1 ; sub(dw,year week,$0) }
else if ( int(week) < variance ) { week=mweek - (variance - week) ; year=year-1 ; sub(dw,year week,$0) }
else { week=sprintf("%02d",week - variance) ; sub(dw,year week,$0) }
} 1

Be sure other fields in line do not match P<year week regex>, since we are using $0

Please, read about NF, RSTART, RLENGTH here (for gawk, but is available on other awk(s) as well ) :
ftp://ftp.gnu.org/pub/old-gnu/Manual...11.html#SEC110


Regards
Peasant.
Last edited by Peasant; 11-02-2018 at 01:02 PM..
This User Gave Thanks to Peasant For This Post:
arunkumar_mca
 

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LEARN ABOUT REDHAT

cal

CAL(1)							    BSD General Commands Manual 						    CAL(1)

NAME

     cal -- displays a calendar

SYNOPSIS

     cal [-smjy13] [[month] year]

DESCRIPTION

     Cal displays a simple calendar.  If arguments are not specified, the current month is displayed.  The options are as follows:

     -1      Display single month output.  (This is the default.)

     -3      Display prev/current/next month output.

     -s      Display Sunday as the first day of the week.  (This is the default.)

     -m      Display Monday as the first day of the week.

     -j      Display Julian dates (days one-based, numbered from January 1).

     -y      Display a calendar for the current year.

     A single parameter specifies the year (1 - 9999) to be displayed; note the year must be fully specified: ``cal 89'' will not display a calen-
     dar for 1989.  Two parameters denote the month (1 - 12) and year.	If no parameters are specified, the current month's calendar is displayed.

     A year starts on Jan 1.

     The Gregorian Reformation is assumed to have occurred in 1752 on the 3rd of September.  By this time, most countries had recognized the ref-
     ormation (although a few did not recognize it until the early 1900's.)  Ten days following that date were eliminated by the reformation, so
     the calendar for that month is a bit unusual.

HISTORY

     A cal command appeared in Version 6 AT&T UNIX.

OTHER VERSIONS

     Several much more elaborate versions of this program exist, with support for colors, holidays, birthdays, reminders and appointments, etc.
     For example, try the cal from http://home.sprynet.com/~cbagwell/projects.html or GNU gcal.

BSD
								   June 6, 1993 							       BSD
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