How can I get the Today -2 days (the last 2 working days from now)? but skipping the weekend?
Example #1: Today is February 25, I want February 21
Example #2: Today is February 26, I want February 24
PS: Date format is DD/MM/YYYY
I have this, but the result is going forward, should I use datediff or what?:
<%
Dim d
d = DateAdd("m", 1, Now)
d = "01/" & Month(d) & "/" & Year(d)
d = DateAdd("d", -1, d)
If Weekday(d) = 7 Then
d = DateAdd("d", -1, d)
ElseIf Weekday(d) = 1 Then
d = DateAdd("d", -2, d)
End If
Response.Write "Day: " & d
%>
To get your desired result you need to subtract 3 days on Saturdays, 4 days on Sundays and Mondays, and 2 days on all other days. This can be achieved with something like this:
today = Now
num = Weekday(today, vbWednesday)
d = today - (2 + num\5 + num\6)
response.write "Two working days back: " & d
The Weekday function returns a numeric value for each weekday. By basing the week on Wednesday you can calculate the additional number of days you need to subtract from the current date with integer divisions:
num\5 returns 1 for Saturday, Sunday and Monday, and 0 otherwise.
num\6 returns 1 for Sunday and Monday, and 0 otherwise.
Thus the term 2 + num\5 + num\6 becomes 3 for Saturdays, 4 for Sundays and Mondays, and 2 for all other days.
This might be overkill for what you need but here are two routines I use in my scripts to add or subtract workdays while considering weekends and holidays.
Function AddWorkingDays(dtStart, intDays)
' Start/Default case...
AddWorkingDays = CDate(dtStart)
' If positive days, step forward, otherwise step backward...
Dim intStep, intCount
If intDays > 0 Then intStep = 1 Else intStep = -1
Do While intCount <> intDays
AddWorkingDays = AddWorkingDays + intStep
If IsValidDate(AddWorkingDays) Then intCount = intCount + intStep
Loop
End Function
Function IsValidDate(d)
Dim intWeekday, intMonth, intDay
intWeekday = Weekday(d)
intMonth = Month(d)
intDay = Day(d)
' Weekend dates are not acceptable...
If intWeekday = vbSaturday Or intWeekday = vbSunday Then Exit Function
' Holidays are also not acceptable...
If intMonth = 01 Then If intDay = 01 Then Exit Function ' New Year's Day
If intMonth = 07 Then If intDay = 04 Then Exit Function ' Independence Day
If intMonth = 12 Then If intDay = 25 Then Exit Function ' Christmas Day
' Memorial Day is the last Monday in May...
If intWeekday = vbMonday Then If intMonth = 05 Then If intDay >= 25 Then Exit Function
' ... (Thanksgiving, others) ...
' All tests passed. Date is a valid workday...
IsValidDate = True
End Function
Related
I want to display the weeks dates based on a week number that I get from my db.
So if I get week=43 then it would display all 7 dates for that week.
Like this.
M=23
T=24
W=25
T=26
F=27
S=28
S=29
Have tested with a lot of date formating but I can't get it working.
So any input really appreciated, thanks!
I ended up with this, works perfect!
currentDate = Date
weekNumber=DatePart("ww", currentDate, vbMonday, vbFirstFourDays)
y = Year(Date)
Public Function FirstDayOfWeek(Year, Week)
Dim TempDate
TempDate = DateSerial(Year, 1, 1)
Do Until DatePart("ww", TempDate, vbMonday, vbFirstFourDays) = 1
TempDate = TempDate + 7
Loop
TempDate = TempDate + (7 * (Week - 1))
FirstDayOfWeek = TempDate - Weekday(TempDate, vbMonday) + 1
End Function
Dim startDatum
Dim slutDatum
startDatum = FirstDayOfWeek(y, weekNumber)
slutDatum = startDatum + 6
mon=DatePart("d", startDatum)
tus=DatePart("d", startDatum+1)
wen=DatePart("d", startDatum+2)
tur=DatePart("d", startDatum+3)
fri=DatePart("d", startDatum+4)
sat=DatePart("d", startDatum+5)
sun=DatePart("d", startDatum+6)
Well, there isn't really an inverse DatePart() function, so you have to make your own calculations.
dim w, wd, y, m, i
y = Year(Date) '- year of the week in question; I'm using today's date
w = 43
wd = DateAdd("d",w*7,CDate("1/1/" & y)) '- adjust as needed for 1st week of year
m = DateAdd("d",2-Weekday(wd),wd) '- find Monday of week
Hopefully, you can go from there.
I have a variable with a date table that looks like this
* table:
[day]
* number: 15
[year]
* number: 2015
[month]
* number: 2
How do I get the days between the current date and the date above? Many thanks!
You can use os.time() to convert your table to seconds and get the current time and then use os.difftime() to compute the difference. see Lua Wiki for more details.
reference = os.time{day=15, year=2015, month=2}
daysfrom = os.difftime(os.time(), reference) / (24 * 60 * 60) -- seconds in a day
wholedays = math.floor(daysfrom)
print(wholedays) -- today it prints "1"
as #barnes53 pointed out could be off by one day for a few seconds so it's not ideal, but it may be good enough for your needs.
You can use the algorithms gathered here:
chrono-Compatible Low-Level Date Algorithms
The algorithms are shown using C++, but they can be easily implemented in Lua if you like, or you can implement them in C or C++ and then just provide Lua bindings.
The basic idea using these algorithms is to compute a day number for the two dates and then just subtract them to give you the number of days.
--[[
http://howardhinnant.github.io/date_algorithms.html
Returns number of days since civil 1970-01-01. Negative values indicate
days prior to 1970-01-01.
Preconditions: y-m-d represents a date in the civil (Gregorian) calendar
m is in [1, 12]
d is in [1, last_day_of_month(y, m)]
y is "approximately" in
[numeric_limits<Int>::min()/366, numeric_limits<Int>::max()/366]
Exact range of validity is:
[civil_from_days(numeric_limits<Int>::min()),
civil_from_days(numeric_limits<Int>::max()-719468)]
]]
function days_from_civil(y, m, d)
if m <= 2 then
y = y - 1
m = m + 9
else
m = m - 3
end
local era = math.floor(y/400)
local yoe = y - era * 400 -- [0, 399]
local doy = math.modf((153*m + 2)/5) + d-1 -- [0, 365]
local doe = yoe * 365 + math.modf(yoe/4) - math.modf(yoe/100) + doy -- [0, 146096]
return era * 146097 + doe - 719468
end
local reference_date = {year=2001, month = 1, day = 1}
local date = os.date("*t")
local reference_days = days_from_civil(reference_date.year, reference_date.month, reference_date.day)
local days = days_from_civil(date.year, date.month, date.day)
print(string.format("Today is %d days into the 21st century.",days-reference_days))
os.time (under Windows, at least) is limited to years from 1970 and up. If, for example, you need a general solution to also find ages in days for people born before 1970, this won't work. You can use a julian date conversion and subtract between the two numbers (today and your target date).
A sample julian date function that will work for practically any date AD is given below (Lua v5.3 because of // but you could adapt to earlier versions):
local
function div(n,d)
local a, b = 1, 1
if n < 0 then a = -1 end
if d < 0 then b = -1 end
return a * b * (math.abs(n) // math.abs(d))
end
--------------------------------------------------------------------------------
-- Convert a YYMMDD date to Julian since 1/1/1900 (negative answer possible)
--------------------------------------------------------------------------------
function julian(year, month, day)
local temp
if (year < 0) or (month < 1) or (month > 12)
or (day < 1) or (day > 31) then
return
end
temp = div(month - 14, 12)
return (
day - 32075 +
div(1461 * (year + 4800 + temp), 4) +
div(367 * (month - 2 - temp * 12), 12) -
div(3 * div(year + 4900 + temp, 100), 4)
) - 2415021
end
I am trying to use asp classic to find how many working days (mon - sat) are in the month and how many are left.
any help or pointers greatly appreciated!
Here's how you can find the number of Sundays in a month without iteration. Somebody posted a JavaScript solution a few months back and I ported it to VBScript:
Function GetSundaysInMonth(intMonth, intYear)
dtmStart = DateSerial(intYear, intMonth, 1)
intDays = Day(DateAdd("m", 1, dtmStart) - 1)
GetSundaysInMonth = Int((intDays + (Weekday(dtmStart) + 5) Mod 7) / 7)
End Function
So, your total work days would just be the number of days in the month minus the number of Sundays.
Edit:
As #Lankymart pointed out in the comments, the above function gives you the number of Sundays in the month but it doesn't tell you how many are left.
Here's another version that does just that. Pass in any date and it will tell you how many Sundays are left in the month starting with that date. If you want to know how many Sundays are in a full month, just pass in the first day of the month (e.g., DateSerial(2014, 8, 1)).
Function GetSundaysRemainingInMonth(dtmStart)
intDays = Day(DateSerial(Year(dtmStart), Month(dtmStart) + 1, 1) - 1)
intDays = intDays - Day(dtmStart) + 1
GetSundaysRemainingInMonth = Int((intDays + (Weekday(dtmStart) + 5) Mod 7) / 7)
End Function
Edit 2:
#Cheran Shunmugavel was interested in some specifics about how this works. First, I just want to restate that I didn't develop this method originally. I just ported it to VBScript and tailored it to the OP's requirement (Sundays).
Imagine a February during a leap year. We have 29 days during the month. We know from the start that we have four full weeks, so each weekday will be represented at least four times. But that still leaves one addition day that's unaccounted for (29 Mod 7 = 1). How do we know if we get an extra Sunday from that one day? Well, in this case, it's pretty simple. Only if our start date is a Sunday can we count an extra Sunday for the month.
What if the month has 30 days? Then we have two extra days to account for. In that case, the start date can be a Saturday or a Sunday and we can count an extra Sunday for the month. And so it goes. So we can see that if we're X additional days within an upcoming Sunday, we can count an extra Sunday.
Let's put this in tabular form:
Addl Days Needed
Day To Count Sunday
---------- ----------------
Sunday 1
Saturday 2
Friday 3
Thursday 4
Wednesday 5
Tuesday 6
Monday 7
So what we need is a formula that we can apply to these situations so that they all result in the same value. We'll need to assign some value to each day and combine that value with the number of addition days needed for Sunday to count. Seems reasonable that if we assign an inverse value to the weekdays and add that to the number of additional days, we can get the same result.
Addl Days Needed Value Assigned
Day To Count Sunday To Weekday Sum
---------- ---------------- -------------- ---
Sunday 1 6 7
Saturday 2 5 7
Friday 3 4 7
Thursday 4 3 7
Wednesday 5 2 7
Tuesday 6 1 7
Monday 7 0 7
So, if weekday_value + addl_days = 7 then we count an extra Sunday. (We'll divide this by 7 later to give us 1 additional Sunday). But how do we assign the values we want to the weekdays? Well, VBScript's Weekday() function already does this but, unfortunately, it doesn't use the values we need by default (it uses 1 for Sunday through 7 for Saturday). We could change the way Weekday() works by using the second param, or we could just use a Mod(). This is where the + 5 Mod 7 comes in. If we take the Weekday() value and add 5, then mod that by 7, we get the values we need.
Day Weekday() +5 Mod 7
---------- --------- -- -----
Sunday 1 6 6
Saturday 7 12 5
Friday 6 11 4
Thursday 5 10 3
Wednesday 4 9 2
Tuesday 3 8 1
Monday 2 7 0
That's how the + 5 Mod 7 was determined. And, with that solved, the rest is easy(er)!
#Zam is on the right track you need to use WeekDay() function, here is a basic idea of how to script it;
<%
Dim month_start, month_end, currentdate, dayofmonth
Dim num_weekdays, num_past, num_future
Dim msg
'This can be configured how you like even use Date().
month_start = CDate("01/08/2014")
month_end = DateAdd("d", -1, DateAdd("m", 1, month_start))
msgbox(Day(month_end))
For dayofmonth = 1 To Day(month_end)
currentdate = CDate(DateAdd("d", dayofmonth, month_start))
'Only ignore Sundays
If WeekDay(currentdate) <> vbSunday Then
num_weekdays = num_weekdays + 1
If currentdate <= Date() Then
num_past = num_past + 1
Else
num_future = num_future + 1
End If
End If
Next
msg = ""
msg = msg & "Start: " & month_start & "<br />"
msg = msg & "End: " & month_end & "<br />"
msg = msg & "Number of Weekdays: " & num_weekdays & "<br />"
msg = msg & "Weekdays Past: " & num_past & "<br />"
msg = msg & "Weekdays Future: " & num_future & "<br />"
Response.Write msg
%>
How about using "The Weekday function returns a number between 1 and 7, that represents the day of the week." ?
I want to convert the given year, month and min information to day of year info.
For eg lets say
year 2004, month 2, day 2 = 33rd day of year
how can I do it in matlab?
Get the datenum for Jan 1 of that year, and subtract it from the given yy/mm/dd. For example, today's day of the year:
jan1 = datenum(datestr(now,'yy'),'yy')
now - jan1 + 1
Check the above against here.
For a specific date,
>> yy = 2004; mm = 2; dd = 2;
>> doty = datenum(yy,mm,dd) - datenum(yy,1,0)
doty =
33
i have 2 date picker
Dim pday, eitday, otherday, tpenalty, difday, subpenalty As Integer
difday = Val(L1.Caption) - Val(L2.Caption)
pday = 7
eitday = 8
otherday = difday - eitday
tpenalty = 25
If difday <= pday Then
PENALTY.Caption = 0
ElseIf difday = eitday Then
PENALTY.Caption = tpenalty
ElseIf difday > eitday Then
For i = 0 To otherday - 1
subpenalty = subpenalty + 5
Next i
PENALTY.Caption = tpenalty + subpenalty
End If
the problem is when the month is change the calculation is invalid.
I'm guessing based on your code (as many things are unclear), but this should give the number of days between two dates:
difday = DateDiff("d", StartDate, EndDate)
I've used StartDate and EndDate to signify the start and end of the lone period which are used to set L1 and L2, as you shouldn't be converting from strings to dates for calculations.