I have an application collecting credit card data. Before sending the information out to the payment entity I am trying to make sure the information entered is, at least, valid. I already worked out the card number and cvv numbers but I am not so sure about the expiry date. The format I get the info is MMYY. So what I am doing is:
-- Simple function to get current date and times
function getdatetime(tz)
local tz = tz or 'America/New_York';
local luatz = require 'luatz';
local function ts2tt(ts)
return luatz.timetable.new_from_timestamp(ts);
end
local utcnow = luatz.time();
local time_zone = luatz.get_tz(tz);
local datetime_raw = tostring(ts2tt(time_zone:localise(utcnow)));
local year, month, day, hour, min, sec, time_reminder = string.match(datetime_raw, "^(%d%d%d%d)%-(%d%d)%-(%d%d)[Tt](%d%d%.?%d*):(%d%d):(%d%d)()");
return year, month, day, hour, min, sec;
end
local current_year, current_month = getdatetime() -- Get current year/Month
local card_expiry_date = 'YYMM'; -- In the app this actually get a value eg: 2204, 2301, 2010, etc.
local card_exp_year = string.sub(card_expiry_date , 3, 4)
local card_exp_month = string.sub(card_expiry_date , 1, 2)
-- Extract the last two digits of the Year
current_year = string.sub(current_year , 3, 4)
-- Check month is valid
if(card_exp_month < '01' or card_exp_month > '12')then
print("This is not a valid month")
else
-- Check date is this month or after
if((card_exp_year < current_year) or (card_exp_year == current_year and card_exp_month < current_month))then
print("Date cannot be before this month.")
else
print("All is good.")
end
end
I do not know if this is the most elegant solution but it works. However it has a huge bug: it will fail at the end of the century. Since I only know the last two digits of the expiry date year, if a card expires in 2102 for instance and we were in 2099 my logic would wrongly reject the date (02 is less than 99).
I am very aware that me an my simple app will likely not be around by then but it bugs me to leave it like this.
Can anyone please suggest a proper way to do this validation?
Thank you!
Wilmar
Credit cards usually expire within a few years. 3 years is average according to some quick web search. Also the owner of a century only card can be safely assumed to be dead and so is his card account.
So when you get a card with 02 in 2099 there is only one reasonable option.
Calculate two differences and pick the smaller one.
Something like local expiresIn = math.min(math.abs(99-2), math.abs(99-102))
Related
In my cube, I have several measures at the day grain that I'd like to sum at the day grain but average (or take latest) at the month grain or year grain.
Example:
We have a Fact table with Date and number of active subscribers in that day (aka PMC). This is snapshotted per day.
dt
SubscriberCnt
1/1/22
50
1/2/22
55
This works great at the day level. At the month level, we don't want to sum these two values (count = 105) because it doesn't make sense and not accurate.
when someone is looking at month grain, it should look like this - take the latest for the month. (we may change this to do an average instead, management is still deciding)
option 1 - Take latest
Month-Dt
Subscribers
Jan-2022
55
Feb-2022
-
option 2 - Take aveage
Month-Dt
Subscribers
Jan-2022
52
Feb-2022
-
I've not been able to find the right search terms for this but this seems like a common problem.
I added some sample data at the end of a month for testing:
dt
SubscriberCnt
12/30/21
46
12/31/21
48
This formula uses LASTNONBLANKVALUE, which sorts by the first column and provides the latest value that is not blank:
Monthly Subscriber Count = LASTNONBLANKVALUE( 'Table'[dt], SUM('Table'[SubscriberCnt]) )
If you do an AVERAGE, a simple AVERAGE formula will work. If you want an average just for the current month, then try this:
Current Subscriber Count =
VAR _EOM = CLOSINGBALANCEMONTH( SUM('Table'[SubscriberCnt]), DateDim[Date] )
RETURN IF(_EOM <> 0, _EOM, AVERAGE('Table'[SubscriberCnt]) )
But the total row will be misleading, so I would add this so the total row is the latest number:
Current Subscriber Count =
VAR _EOM = CLOSINGBALANCEMONTH( SUM('Table'[SubscriberCnt]), DateDim[Date] ) //Get the number on the last day of the month
VAR _TOT = NOT HASONEVALUE(DateDim[MonthNo]) // Check if this is a total row (more than one month value)
RETURN IF(_TOT, [Monthly Subscriber Count], // For total rows, use the latest nonblank value
IF(_EOM <> 0, _EOM, AVERAGE('Table'[SubscriberCnt]) ) // For month rows, use final day if available, else use the average
)
In the project I'm working on I have a daily command that basically checks the date of the last record in the database and tries to fetch data from an API from the day after and then each month after that (the data is published monthly).
Basically, the last record's date is 2019-08-30. I'm mocking as if I were running the task on 2019-09-01 with
$test = Carbon::create(2019,9,1,4);
Carbon::setTestNow($test);
I then create a monthly period between the next day of the last record's date and the last day of the current month like so:
$period = CarbonPeriod::create($last_record_date->addDay(), '1 month', $last_day_of_current_month);
Successfully generating a period with start_date = 2019-08-31 and end_date = 2019-09-30. Which I use in a simple foreach.
What I expected to happen is that it runs twice, once for August and once for September, but it's running only once for the start date. It's probably adding a month and going past the end date, but I don't know how to force the behaviour I'm looking for.
TL;DR:
$period = CarbonPeriod::create('2019-08-31', '1 month', '2019-09-30');
foreach ($period as $dt) {
echo $dt->format("Y-m") . "<br>\n";
}
This will print just 2019-08, while I expect 2019-08 and 2019-09. What's the best way to achieve that?
Solution :-
You can store actual date in $actual_day and current date for occurring monthly in $current_day. Put a check on comparing both dates, if not matched then make it on the same day it will skip 30,31 case in case of February month.
$current_date = $current_date->addMonths(1);
if($current_date->day != $actual_day){
$date = Carbon::parse($date->year."-".$date->month."-".$actual_day);
}
Your start date is 2019-08-31. Adding a month takes you to 2019-09-31. 2019-09-31 doesn't exist so instead you get 2019-10-01, which is after your end date. To avoid this I'd suggest you use a more regular interval such as 30 days.
Otherwise you're going to have to rigorously define what you mean by "a month later". If the start date is 31st Jan is the next date 28th February? Is the month after 28th or 31st March? How do leap years affect things?
I have a panel data set for multiple waves (13) for roughly 10,000 individuals each year, with people entering and exiting at various time points. I am interested in what happens as people become diagnosed with a disease over time. Therefore I need to recode the time variable so that it becomes t=0 the first wave when diagnosed, then t=1 is the next year and so on, so that all of my individuals are comparable (and I guess -1 for t-1 etc). However I am unsure about how to go about this in stata. Would anyone be able to advise? Many thanks
The case of one diagnosis per person
clear all
set more off
*----- example data -----
set obs 100
set seed 2357
generate id = _n
generate year = floor(10 * runiform()) + 1990
expand 5
bysort id: replace year = year + _n
bysort id (year): generate diag = cond(_n == 3, 1, 0)
list in 1/20, sepby(id)
*----- what you seek -----
bysort id (diag): gen time = year - year[_N]
sort id year
list in 1/20
I assume the same data structure as #RichardHerron and use his example. diag is an indicator variable that takes on the value of 1 at the time of diagnosis and 0 otherwise (only one diagnosis per person is considered).
The sorting done by bysort is critical. The observation holding the time of diagnosis is pushed to the end of the database (by id groups) and then all that's left to do is compare (subtract) all years with that reference year. See help _variables for details on system variables like _N.
The case of multiple diagnoses per person
If several diagnoses are made per person, but we care only for the first occurence (according to year), we could do:
gsort id diag -year
by id: gen time = year - year[_N]
Simple but not optimal solution
Suppose diagnosis is 1 when diagnosed (at most once per person) and 0 otherwise.
Then the time at diagnosis is at its simplest
egen time_diagnosis = total(diagnosis * year), by(id)
but you need to ignore any zeros. To spell that out,
replace time_diagnosis = . if time_diagnosis == 0
Better alternative
A more complicated but preferable alternative can handle multiple diagnoses if they occur:
egen time_diagnosis = min(year / diagnosis), by(id)
as year / diagnosis is year when diagnosis is 1 and missing otherwise. This yields missing values if there is no diagnosis, which is as it should be.
Then you subtract that to get a new time variable.
gen time2 = time - time_diagnosis
In short, I think you can get this done in two statements, handling panel structure too.
Update
#Richard Herron asks why use egen with by(), and not just
gen time_diagnosis = time * diagnosis
A limitation of that is that the "correct" value is contained only in those observations for which diagnosis is 1; that value still has to be "spread" to other values for the same id. But that is precisely what egen does here. In the simplest situation, with one diagnosis the total of time * diagnosis is just time * 1 or time, as any zeros make no difference to the sum.
It is usually helpful to provide test data, but here they are easy enough to generate. The trick is to find the first year for each individual (my fyear), which I'll do with min() from egen. Then I'll subtract this first year fyear from the actual year to find the year relative to diagnosis ryear.
/* generate panel */
clear
set obs 10000
generate id = _n
generate year = floor(10 * runiform()) + 1990
expand 10
bysort id: replace year = year + _n
sort id year
list in 1/20
/* generate relative year */
bysort id: egen fyear = min(year)
generate ryear = year - fyear
list in 1/20
If the first year in the panel is not diagnosis, then just construct fyear based on diagnosis criteria.
Edit: Thinking more on this, maybe it's the last part that you're having a hard time with (i.e., identifying the diagnosis year to subtract from the calendar year). Here's what I would do.
bysort id (year): generate diagnosis = cond(_n == 5, 1, 0)
preserve
tempfile diagnosis
keep if (diagnosis == 1)
rename year dyear
keep id dyear
save `diagnosis'
restore
merge m:1 id using `diagnosis', nogenerate
generate ryear2 = year - dyear
I have a jquery calendar for the start date of a project.
Using Watir (automated browser driver, a gem for ruby), I have a set date that I would like to enter in.
The calendar start date is always today's date, whatever that may be for the day it is used. I was wondering if there was a way that ruby can process what today's date is, and use the specified date provided by the user, to calculate the difference of months between them.
Here is an example of the Calendar plugin: http://jqueryui.com/datepicker/
example:
today's date is 30/10/2012, if there was a project that were to start on the 20/12/2012, that would be 2 months from now, so 2 clicks on the next month button.
Is there a way I could do this?
Here is how I approached a similar situation with JSdatepicker:
$today = Time.now.strftime("%e").gsub(" ", "") #one digit day of month without leading space
#browser.text_field(:id => /dateAvailable/).click
Watir::Wait.until(60) {#browser.div(:id => /dateAvailable_popup_cal/).td(:text => $today).exists?}
#browser.div(:id => /dateAvailable_popup_cal/).td(:text => $today).click
Set or grab the date.
Click the text_field that fires the JSDatePicker object
Wait until the calendar actually pops up
The current month is shown, so choose today's date number.
In your case, you also need to set the month. Whether prompting the user for this, or choosing "today", the theory is the same:
$month = Date::MONTHNAMES[Date.today.month] #etc
Pseudo-code making lots of assumptions (only future dates, month name shown on calendar as text, etc):
while !#jquerytablewindow.text.include?($month)
next_month_button.click
end
I don't see a specific advantage to my method versus counting each month, unless of course we add a month to the calendar one day and you still want your code to work!
You could do:
#End date converted to date object
specified_date = '20/12/2012'
end_date = Date.parse(specified_date)
#Start date (today - 30/10/2012)
today = Date.today
#Determine difference in months
number_of_months_up_to_today = (today.month + today.year * 12)
number_of_months_up_to_end = (end_date.month + end_date.year * 12)
clicks_required = number_of_months_up_to_end - number_of_months_up_to_today
#=> 2
Basically it is counting the number of months since the year 0 and then finding the difference.
I have an object which contains a list of due dates, I am trying to build a system which returns the due date when a specified date is 1 month or less before the due date. It should return the due date in this format "1st Feb 2009". Let me clarify, using my current code
#Build array of estate objects
estate.due_dates = "1st Feb, 3rd May, 1st Aug, 5th Nov"
estate2.due_dates = "28th Feb, 31st May, 31st Aug, 30th Nov"
estates = [estate,estate2]
set_due_date_on_estates("1st Jan 2009",estates) #Run function - should return "1st Feb 2009,28th Feb 2009"
def set_due_date_on_estates(date,estates)
estates.each{|estate|
estate.due_dates.split(",").each{|due_date|
((date)..(date >> 1)).each{|current_date|
estate.set_reminder(due_date + current_date.strftime("%Y")) if current_date.strftime('%d %m') ==
Date.parse(due_date).strftime('%d %m')
}
}
end
}
The issue I am having, is that my list of due dates doesnt have a Year, so I am looping through my range and checking if the dates are equal using the format "%d %m". If so I am setting the reminder in the estate object by using the current "due date" in the loop concatenated with the Year of the "current date" in the loop.
Am not too happy with the code, in particular the nested loops and wondered if there was a better way I could deal with checking that the due_dates where in the date range, even though the due_dates dont have a year. Thanks
You could use date parsers: Kronos, chronic
Example for kronos:
def parse_date(date)
Kronos.parse(date.sub(/\d{4}$/, ''))
end
This function gives you a Kronos object without year which is more easily to compare, build range and so on.
Yes you can use Chronic and also you can write a worker which will keep checking if the specified date is 1 month or less before the due date at regular interval. And ask that worker to do something if result is true (say send you an email or anything if date is within due date) you can find more information about worker by googling Resque and Redis. Another option would be to convert both dates on some base reference and then do the calculations.