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**All_Is_Number****Member**- Registered: 2006-07-10
- Posts: 258

Today is 22/7, in case you might have missed it.

*You can shear a sheep many times but skin him only once.*

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**Devantè****Real Member**- Registered: 2006-07-14
- Posts: 6,400

Didn't realise...a day hard to remember. That is, unless you're a computer or a robot that can store the value of 22/7. Nice find.

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**MathsIsFun****Administrator**- Registered: 2005-01-21
- Posts: 7,685

LOL! Is it marked on your calendar?

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman

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**All_Is_Number****Member**- Registered: 2006-07-10
- Posts: 258

MathsIsFun wrote:

LOL! Is it marked on your calendar?

:D:D

Actually, I happened across the information while checking out Pi on Wikipedia when looking at the Pi thread in the Cool forum. I noticed that it was today, so I thought I would let everyone here know.

Most days I couldn't tell you what the date is!

*You can shear a sheep many times but skin him only once.*

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**MathsIsFun****Administrator**- Registered: 2005-01-21
- Posts: 7,685

This wonderful day has rolled around again ... "Happy Pi Approximation Day"!

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman

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**Devantè****Real Member**- Registered: 2006-07-14
- Posts: 6,400

Happy 'Pi Approximation Day', everyone!

Has been a year since I last posted in this thread, and I can't believe I'm saying this again!

Yes, it is hard to remember.

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**mikau****Member**- Registered: 2005-08-22
- Posts: 1,504

but pi itself actually occurs somewhere between 21/7 and 22/7.

Ya know, pi is a great number but there are other really important numbers worthy of notice! take for instance, 1 day. It occurs exactly 1 month and 1 day appart except for one month.

What about e or Phi?

Holy crud! I just wrote a simple program and i found the best e approximation day on the calender is the 19th of july! Thats just 3 days before the best pi approximation day!!

Also, the best phi approximation day appears to be the 13th of august . Also not far away!

Kind of scary that pi day, e day, phi day and a 1 day all occur within a month of eachother.

Its very depressing that there isn't a 0 day though. But I guess, if we're talking about approximatons, best approximation is january 31st. 1/31 (though we put month first that time)

Hmm.. I guess we could pick some random day and imagine it to be i day. I say it should be february 29th.

*Last edited by mikau (2007-07-23 05:55:43)*

A logarithm is just a misspelled algorithm.

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**mikau****Member**- Registered: 2005-08-22
- Posts: 1,504

And for anyone who cares, here's a java program to find any 'X approximation day'

```
import java.util.*;
public class Calanderfraction
{
public static void main(String[] args)
{
// program to prompt the user to enter some constant
// the program finds the day/month ratio that
// best approximates that constant
// prompt the user to enter a constant
Scanner console = new Scanner(System.in);
System.out.print(" Enter the constant to search for: ");
final double SEARCHED_CONSTANT = console.nextDouble();
// set the maximum number of days for each month, considering leap years as well
int[] daysInMonth = {31, 29, 31, 30, 31, 30, 31,31,30,31,30,31};
// variable to store the ratio of day/month.
//initialize to an arbitrary value
double fraction = 1;
// variable to store the difference of fraction and SEARCHED_CONSTANT for any date
// initialize to some arbitrary value
double smallestDifference = 10;
// variable to hold the best approximation of SEARCHED_CONSTANT found thus far
//initialize to an arbitrary value
double best = 1;
// variables to hold the integer numerator and denominator of 'best'
//initialize to arbitrary values
int num = 1, den = 1;
// process all 12 months
for (int month = 1; month <= 12; month++)
{
// for each month, process each day
for (int day = 1; day <= daysInMonth[month-1]; day++)
{
// determine the fraction of day/month
fraction = (double)(day)/(double)(month);
// if this is a better approximation of SEARCHED_CONSTANT
if (Math.abs(fraction - SEARCHED_CONSTANT) < smallestDifference)
{
// update the best values
num = day;
den = month;
smallestDifference = Math.abs(fraction - SEARCHED_CONSTANT);
best = fraction;
}
} // end for. go to next month
} // end for. all months have passed
// print the best day/month ratio found in fraction form, and its decimal value
System.out.println("\nThe best calendar approximation for " + SEARCHED_CONSTANT + " is "
+ num + "/" + den + " = " + best);
} // end main
} // end class
```

A logarithm is just a misspelled algorithm.

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