CF to run through a list of dates and count number of time in specified range.

[MuonDude]

I am trying to creat a CF to do the following

given:

Input:

startDate = starting date for range

endDate = ending date for range

dateList = list of dates we would like to test

count = initial value of 0

Output:

count of the number of times a date from dateList falls within the range [startDate, endDate]

parse each element of the list: dateList (a list of dates) to check if startDate <= currentDate <= endDate, if it is increment counter by 1

dateList is a return separated list of dates (MM/DD/YYYY).

I'm familar with recursion, but can't seeem to get my head around this. I also wonder if someone else has already developed this CF.

It is of course trival when dateList is a single element list. The problem I'm having is with the recursion. I stuck with how to recursively walk the dateList and keep track of tne count of how

many times a date from dateList falls within the range.

TIA

[comment]

It seems simple enough:

Let ( [

item = GetValue ( dateList ; counter ) ;

iDate = GetAsDate ( item ) ;

test = startDate ≤ iDate and iDate ≤ endDate

] ;

Case ( counter ≤ ValueCount ( dateList ) ; test + ThisFunction ( startDate ; endDate ; dateList ; counter + 1 ) )

)

If your file/system is NOT set up to use MM/DD/YYYY, do a proper text parse to get the date using the Date() function. You would call this function with 1 as the initial counter value.

[MuonDude]

It seems simple enough:

Let ( [

item = GetValue ( dateList ; counter ) ;

iDate = GetAsDate ( item ) ;

test = startDate ≤ iDate and iDate ≤ endDate

] ;

Case ( counter ≤ ValueCount ( dateList ) ; test + ThisFunction ( startDate ; endDate ; dateList ; counter + 1 ) )

)

If your file/system is NOT set up to use MM/DD/YYYY, do a proper text parse to get the date using the Date() function. You would call this function with 1 as the initial counter value.

I figured it had to be simple, but the counter was messing me up.

Thanks very much. regards.

[Raybaudi]

Hi

this is another way to do the same thing without the fourth parameter ( and it works on FM 7 too )

cf ( dateList ; startDate ; endDate )

Let([

firstRow = GetAsDate ( LeftValues ( dateList ; 1 ) );

next = RightValues ( dateList; ValueCount ( dateList ) - 1 )

];

Case(

not IsEmpty ( firstRow ) and not IsEmpty ( startDate ) and not IsEmpty ( endDate );

Case(

firstRow ≥ startDate and firstRow ≤ endDate ; 1 + cf ( next ; startDate ; endDate );

0 + cf ( next ; startDate ; endDate )

);

""

)

)

[MuonDude]

Hi

this is another way to do the same thing without the fourth parameter ( and it works on FM 7 too )

...snip...

Very cool. Thank you. Both approaches really helped.

I'm still getting used to thinking recursively

as I'm so used to programming in other languages

with loop constucts.

cheers!