Date to Day

Pretty sure this is correct. Feel free to test it out a bit...

This will change a date mm/dd/yy to the day of the week.

integer dayofweek;
integer m=9;  //Jokey Domela's Birthday!
integer d=15;
integer y=6;
integer z;
list days = ["Sunday","Monday","Tuesday","Wednesday","Thursday","Friday","Saturday"];

mathit()
{
    if (m < 3)
    {
        z = y - 1;
    }
    else
    {
        z = y;
    }
    dayofweek = ( llFloor(23 * m/9) + d + 4 + y + llFloor(z/4) - llFloor(z/100) + llFloor(z/400))%7;
    if (m >= 3)
    {
        dayofweek = dayofweek - 2;
    }
}

default
{
    state_entry()
    {
        mathit();
        string day = llList2String(days, dayofweek); 
        llSay(0,(string)day);
    }
}

Now that we can get the unix time of day, a much simpler formula for the day of week is available. (Note this code only calculates current day of week)

list days = ["Sunday","Monday","Tuesday","Wednesday","Thursday","Friday","Saturday"];

// Returns day of week (PST), with 0 = Sunday
integer day_of_week()
{
    integer time = llGetUnixTime();
    
    // Convert to server timezone, regardless of before or after midnight
    if(llGetWallclock() < llGetGMTclock()) {
        time -= (integer) (llGetGMTclock() - llGetWallclock());
    } else {
        time -= 86400 + (integer) (llGetGMTclock() - llGetWallclock());
    }
    
    return llFloor((time / 86400) - 3) % 7;
} 

default
{
    state_entry()
    {
        string day = llList2String(days, day_of_week());
        llSay(0,(string)day);
    }
} 

I release the above code to the public domain, feel free to license it however you wish.

--Bleu Drake