topic Re: Find every Thursday in a year? in Operating System - HP-UX

Find every Thursday in a year?

Steve Start — Tue, 12 Oct 2004 13:55:05 GMT

Hi,

Does anybody know how to get date or cal to show every Thursday in a year?

Thanks,
Steve

Re: Find every Thursday in a year?

Steven E. Protter — Tue, 12 Oct 2004 13:58:23 GMT

This tool can do it:

http://www.hpux.ws/merijn/caljd-2.23.sh

http://www.hpux.ws/merijn/caljd-2.2.pl

You'll need to read the notes to learn how to give the tool input.

A. Clay's date magic tool!

It can do all kinds of date magic. Bookmark it, its updated periodically. I've ported it to Linux(shell change).

SEP

Re: Find every Thursday in a year?

A. Clay Stephenson — Tue, 12 Oct 2004 14:07:03 GMT

When combined with the above mentioned caljd.sh (with caljd.sh installed somewhere in your PATH) this untested and typed "on the fly" script should do it.

#!/usr/bin/sh

typeset PROG=${0##*/}

usage()
{
echo "\n${PROG}: year wkday\n" >&2
echo "year - 4-digit year" >&2
echo "wkday: 0 - Sun, 1 - Mon, ... 6 - Sat\n" >&2
return 255
} # usage

typeset -i STAT=0
if [[ ${#} -ge 2 ]]
then
typeset -i YR=${1}
typeset -i WKDAY=${2}
shift 2
typeset -i JDAY1=$(caljd.sh 1 1 ${YR})
typeset -i WDAY1=$(caljd.sh -w ${JDAY1})
typeset OFFSET=$((${WKDAY} - ${WDAY1}))
if [[ ${OFFSET} -lt 0 ]]
then
((OFFSET += 7))
fi
typeset -Z4 YEAR=${YR}
typeset -Z2 MONTH=0
typeset -Z2 DAY=0
typeset JD=$((${JDAY1} + ${OFFSET}))
while [[ ${YEAR} -eq ${YR} ]]
do
caljd.sh ${JD} | read MONTH DAY YEAR
if [[ ${YEAR} -eq ${YR} ]]
then
echo "${MONTH}/${DAY}/${YEAR}"
fi
((JD += 7))
done
else
usage
STAT=${?}
fi
exit ${STAT}

-------------------------------------------

Invoke it like this:
weekday.sh 2005 4

The trick is to find the 1st desired weekday in the year and then display every 7th day until the year changes. If I ain't done gone and typed something wrong, this here ought to do it for you.

Re: Find every Thursday in a year?

A. Clay Stephenson — Tue, 12 Oct 2004 14:20:38 GMT

Hi Steve:

To be ultra nit-picky, please make these changes:

typeset OFFSET=$((${WKDAY} - ${WDAY1}))
to
typeset -i OFFSET=$((${WKDAY} - ${WDAY1}))

and

typeset JD=$((${JDAY1} + ${OFFSET}))
to
typeset -i JD=$((${JDAY1} + ${OFFSET}))

The script will work just fine w/o these changes but I tend to be a rigorous kind of guy. I didn't notice anything else.

Re: Find every Thursday in a year?

Steve Start — Tue, 12 Oct 2004 15:40:13 GMT

Thanks, that worked great.

Re: Find every Thursday in a year?

Muthukumar_5 — Tue, 12 Oct 2004 16:09:52 GMT

We can do with cal easily as,

#!/bin/sh

# Input year
year=${1:-2004}
month=1

while [[ $month -le 12 ]]
do

cal $month $year | head -1
cal $month $year | grep -v $year | cut -b 12-14
let month=month+1

done

It will give you informations there.