ries@trwrb.UUCP (Marc Ries) (09/04/86)
[LE]
Dear Netters,
Due to recent requests for Date and Julian Date routines, I went
back thru my archives and dug up these three items. Please note,
I did *not* write these (except for the Makefile). Jdate.c and
jday.c were: Author: Robert G. Tantzen, translator: Nat
Howard. I don't know who did day.c (will the real author please
stand up).
# Cut_Here-----Cut_Here-----Cut_Here---------Cut_Here
#! /bin/sh
# This is a shell archive, meaning:
# 1. Remove everything above the #! /bin/sh line.
# 2. Save the resulting text in a file.
# 3. Execute the file with /bin/sh (not csh) to create:
# Makefile
# day.c
# jday.c
# jdate.c
export PATH; PATH=/bin:/usr/bin:$PATH
echo shar: "extracting 'Makefile'" '(498 characters)'
if test -f 'Makefile'
then
echo shar: "will not over-write existing file 'Makefile'"
else
cat << \RiesES_PIECES > 'Makefile'
#
# Makefile: day
# Created: Thursday, September 04, 1986
# By: Marc Ries
#
CC = /bin/cc
OPTS = -O
DEFS =
CFLAGS = $(OPTS) $(DEFS)
SRCS = day.c jday.c jdate.c
OBJS = jday.o jdate.o
LIBS =
RANLIB = ucb ranlib libjdates.a
all: day libjdates
day: day.o
$(CC) $(CFLAGS) -o day day.c $(LIBS)
libjdates: jday.o jdate.o
ar r libjdates.a $(OBJS)
$(RANLIB)
clean:
rm -f $(OBJS) a.out core
shar:
shar -v day.[1clyh] Makefile > day.shr
edit:
vi $(SRCS)
day.o: day.c
RiesES_PIECES
fi
echo shar: "extracting 'day.c'" '(2674 characters)'
if test -f 'day.c'
then
echo shar: "will not over-write existing file 'day.c'"
else
cat << \RiesES_PIECES > 'day.c'
/* ---------------------------------------------------------------------- */
/* Program to calculate # of days between two dates */
/* ---------------------------------------------------------------------- */
/* Please note that this program only works from 01-12-1600 A.D. onward */
#include <stdio.h>
struct date /* structure to hold date */
{
int month;
int day;
int year;
} date_1;
long int funct1 (y,m) /* part of # of days calc. */
int y, m;
{
long int result;
if ( m <= 2 )
y -= 1;
result = y;
return (result);
}
long int funct2 (m)
int m;
{
long int result;
if ( m <= 2 )
result = m + 13;
else
result = m + 1;
return(result);
}
/* Function to calculate the number of days in dates */
long int day_count (m, d, y)
int m, d, y;
{
long int number;
number = 1461 * funct1(y,m) / 4 + 153 * funct2(m) / 5 + d;
return (number);
}
main ()
{
long int number_of_days1;
int day_of_week, screw_up = 0;
printf("\n\n*****************************************************************\n");
printf("THIS PROGRAM WILL COMPUTE THE DAY OF THE WEEK (SUNDAY - SATURDAY)\n");
printf("\t\tTHAT A GIVEN DATE WILL FALL ON\n");
printf("*****************************************************************\n\n");
printf ("Enter a date (mm dd yyyy) i.e. 03 12 1985 \n");
scanf ("%d %d %d", &date_1.month, &date_1.day, &date_1.year);
number_of_days1 = day_count (date_1.month, date_1.day, date_1.year);
printf ("\nThe date is: " );
day_of_week = (number_of_days1 - 621049) % 7;
switch (day_of_week)
{
case 0 :
printf ("Sunday,");
break;
case 1 :
printf ("Monday,");
break;
case 2 :
printf ("Tuesday,");
break;
case 3 :
printf ("Wednesay,");
break;
case 4 :
printf ("Thursday,");
break;
case 5 :
printf ("Friday,");
break;
case 6 :
printf ("Saturday,");
break;
default:
printf ("Something is screwed up -- Maybee you entered\n");
printf ("a date earlier than 01 12 1600\n\n");
screw_up = 1;
}
printf (" %02d/%02d/%02d\n", date_1.month, date_1.day, date_1.year);
}
RiesES_PIECES
fi
echo shar: "extracting 'jday.c'" '(818 characters)'
if test -f 'jday.c'
then
echo shar: "will not over-write existing file 'jday.c'"
else
cat << \RiesES_PIECES > 'jday.c'
/*
Here are two routines, jday.c and jdate.c.
They are translations from ALGOL in Collected Algorithms of CACM.
*/
/*
** Takes a date, and returns a Julian day. A Julian day is the number of
** days since some base date (in the very distant past).
** Handy for getting date of x number of days after a given Julian date
** (use jdate to get that from the Gregorian date).
** Author: Robert G. Tantzen, translator: Nat Howard
** Translated from the algol original in Collected Algorithms of CACM
** (This and jdate are algorithm 199).
*/
long
jday(mon, day, year)
int mon, day, year;
{
long m = mon, d = day, y = year;
long c, ya, j;
if(m > 2) m -= 3;
else {
m += 9;
--y;
}
c = y/100L;
ya = y - (100L * c);
j = (146097L * c) /4L + (1461L * ya) / 4L + (153L * m + 2L)/5L + d + 1721119L;
return(j);
}
RiesES_PIECES
fi
echo shar: "extracting 'jdate.c'" '(906 characters)'
if test -f 'jdate.c'
then
echo shar: "will not over-write existing file 'jdate.c'"
else
cat << \RiesES_PIECES > 'jdate.c'
/* Julian date converter. Takes a julian date (the number of days since
** some distant epoch or other), and returns an int pointer to static space.
** ip[0] = month;
** ip[1] = day of month;
** ip[2] = year (actual year, like 1977, not 77 unless it was 77 a.d.);
** ip[3] = day of week (0->Sunday to 6->Saturday)
** These are Gregorian.
** Copied from Algorithm 199 in Collected algorithms of the CACM
** Author: Robert G. Tantzen, Translator: Nat Howard
*/
int *
jdate(j)
long j;
{
static int ret[4];
long d, m, y;
ret[3] = (j + 1L)%7L;
j -= 1721119L;
y = (4L * j - 1L)/146097L;
j = 4L * j - 1L - 146097L * y;
d = j/4L;
j = (4L * d + 3L)/1461L;
d = 4L * d + 3L - 1461L * j;
d = (d + 4L)/4L;
m = (5L * d - 3L)/153L;
d = 5L * d - 3 - 153L * m;
d = (d + 5L) / 5L;
y = 100L * y + j;
if(m < 10)
m += 3;
else {
m -= 9;
++y;
}
ret[0] = m;
ret[1] = d;
ret[2] = y;
return(ret);
}
RiesES_PIECES
fi
exit 0
# End of shell archive