Solved

From "01/01/1900" to "monday". How???

Posted on 1999-01-15
5
211 Views
Last Modified: 2010-04-16
Given a date, how can I work out the day of the week?
Since I'm in England and we do dates as dd/mm/yy, I want to enter a date, for example 15/04/1976 and the function to return a value for Thursday (which was the day of the week for 15/04/1976 if I remember). The way I'm thinking would probably work but it would be so long that it would just be dumb to use. No grace or finesse. Come on, astound me.
I think this could be hard so there's 200 points riding on it!
0
Comment
Question by:wierd_dave
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
5 Comments
 

Expert Comment

by:ahTri
ID: 1182312
I'm not really sure to attemp to take the 200 points u offer but i'm thinking of setting a fix date for example today (Saturday, 16/1/1999) calculate the number of days from today to the date u want to query, devide that number to 7, the remain of the division can be calculate to make the Date.

If u think this way work I will send u the set of objects to calculate the number of days from one day to another. Sorry for your 200 points if u not satisfy with this answer
0
 
LVL 84

Expert Comment

by:ozo
ID: 1182313
int dd=1;
int mm=1;
int yy=1900;
int jdn;
char *weekday[]={"Tuesday","Wednesday","THursday","Friday","Saturday","Sunday","Monday"};
if( mm < 3 ){ mm += 12; yy -= 1; }
jdn = dd+1720996+(mm+1)*306/10+yy*365 + yy/4 - yy/100 + yy/400;
printf("%s\n",weeday[jdn%7]);
0
 

Author Comment

by:wierd_dave
ID: 1182314
Sorry ahTri, that was fairly much the way I was thinking. I was going to work out the number of days from 01/01/1900 and use the remainder as you said to get the date.
Rejection seems so negative, but i've tried ozos' method and it is far batter than I would have some up with.
If ozo wants to submit an answer, they can have the 200 points.

Thanks to both of you.
0
 
LVL 1

Expert Comment

by:The_Brain
ID: 1182315
I have written a program to work out what day of the week it is on any specific date, in that there is a function that tells you the day number from 1900...

Well?  Interested?
0
 
LVL 84

Accepted Solution

by:
ozo earned 200 total points
ID: 1182316
char *weekday[]={"Tuesday","Wednesday","Thursday","Friday","Saturday","Sunday","Monday"};
 dd=15;
 mm=4;
 yy=1976;
if( mm < 3 ){ mm += 12; yy -= 1; }
JulianDayNumber = 1721088 + dd + (mm-2)*367/12 + yy*365 + yy/4 - yy/100 + yy/400;
printf("%s\n",weeday[JulianDayNumber%7])
0

Featured Post

Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Many modern programming languages support the concept of a property -- a class member that combines characteristics of both a data member and a method.  These are sometimes called "smart fields" because you can add logic that is applied automaticall…
Basic understanding on "OO- Object Orientation" is needed for designing a logical solution to solve a problem. Basic OOAD is a prerequisite for a coder to ensure that they follow the basic design of OO. This would help developers to understand the b…
The viewer will learn how to use the return statement in functions in C++. The video will also teach the user how to pass data to a function and have the function return data back for further processing.
The viewer will learn additional member functions of the vector class. Specifically, the capacity and swap member functions will be introduced.

695 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question