Hi,

I have a need to replicate the descend function outside of Xbase++ (if 
FoxPro) so I'm trying to create a function which produces the same 
result as the Xbase++ DESCEND().

I believe I have it figured out for data types, "C","L","N" but not for 
Dates.

My initial attempts with this post resulted in the News Server flagging 
it as spam and denying the upload so I have taken the original posting 
and made it a text attachment.  I realize this is non-standard but did 
not know how else to work around the spam flagging.

I you could take a moment and read the attached file perhaps you may be 
able to lend some assistance.

Any assistance would be appreciated!

Thanks... Jonathan

jonathan.leeming@the-family-centre.com
Edmonton, Alberta, Canada

> I believe I have it figured out for data types, "C","L","N" but not for
> Dates.

PROCEDURE MAIN
LOCAL dDate := DATE()
LOCAL dOld  := dDate -10
LOCAL dNew  := dDate +10

CLS

? dDate
? dOld
? dnew
? ""
? DESCEND(dDate)
? DESCEND(dOld)
? DESCEND(dnew)
WAIT

RETURN



---
Diese E-Mail wurde von AVG auf Viren geprüft.
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On 8/21/2019 8:10 PM, Jim Lee wrote:
>> I believe I have it figured out for data types, "C","L","N" but not for
>> Dates.
> 
> PROCEDURE MAIN
> LOCAL dDate := DATE()
> LOCAL dOld  := dDate -10
> LOCAL dNew  := dDate +10
> 
> CLS
> 
> ? dDate
> ? dOld
> ? dnew
> ? ""
> ? DESCEND(dDate)
> ? DESCEND(dOld)
> ? DESCEND(dnew)
> WAIT
> 
> RETURN
> 
> 
> 
> ---
> Diese E-Mail wurde von AVG auf Viren geprüft.
> http://www.avg.com
> 
Hi Jim,

Thanks for the reply.  I currently have no problem using the DESCEND() 
function within Xbase++ but the issue is I'm trying to create a separate 
function in another language that does not have DESCEND().

The objective is to create some code for a function that will return the 
same descend values as the Xbase++ DESCEND().  In the descend.txt file I 
elaborate more and would have included the same in my original message 
but some phrase in my initial message was flagged as spam so I could not 
send the message intact.

I believe the date needs to be converted to some sort of numerical value 
that would also handle every 4th year with the extra day as a leap year. 
  In the code from the H_arbour site that I mentioned in my descend.txt 
attachment there is a "magical" value 5231808.  The date value is 
converted by some yet unknown function and then subtracted from this 
value (5231808) to get the "Descended" value.

Thanks... Jonathan

jonathan.leeming@the-family-centre.com
Edmonton, Alberta, Canada

Jonathan,

The reason for the Spam Flag, is using that name of the programming language 
that is a synonym for Port or Haven. 

Your numbers are off by 30 days, though, at least as far as Xbase++ 2.0.1113 
is concerned.

The Descend calculation routine is quite simple:

5231808 - DtoJ(Date()) is the same as Descend(Date())

The reverse is:

JtoD(5231808 - Descend(Date())

Using today's Date, 08/22/2019, we get the following:

dDate := CtoD('08/22/2019')
? Descend(dDate)        ==> 2773090
? 5231808 - DtoJ(dDate) ==> 2773090

? DtoC(JtoD(5231808 - 2773090)) ==> 08/22/2019

The DtoJ() and JtoD() functions were added to Xbase++ with Version 2.00.832 
and don't exist in earlier versions.

In VFP, you have the functions SYS(10) -- String from Julian Day Number -- 
and SYS(11) -- Julian Day Number from Date -- which might return the same 
values as Xbase++ does, but that would have to be tested.

Hope that helps,

Andreas

Andreas Gehrs-Pahl
Absolute Software, LLC

phone: (989) 723-9927
email: Andreas@AbsoluteSoftwareLLC.com
web:   http://www.AbsoluteSoftwareLLC.com
[F]:   https://www.facebook.com/AbsoluteSoftwareLLC

Jonathan,

Luiz Penna just send me an email and pointed out that you don't need the 
DtoJ() and JtoD() functions to calculate the Descend() value.

You can also simply use:

nDescend := StoD("96120207") - dDate

And the reverse would be:

dDate := StoD("96120207") - nDescend

And all xBase dialects have the StoD() and/or CtoD() functions.

Thanks, Luiz!

Hope that helps,

Andreas

Andreas Gehrs-Pahl
Absolute Software, LLC

phone: (989) 723-9927
email: Andreas@AbsoluteSoftwareLLC.com
web:   http://www.AbsoluteSoftwareLLC.com
[F]:   https://www.facebook.com/AbsoluteSoftwareLLC

On 8/22/2019 6:49 AM, Andreas Gehrs-Pahl wrote:
> Jonathan,
> 
> Luiz Penna just send me an email and pointed out that you don't need the
> DtoJ() and JtoD() functions to calculate the Descend() value.
> 
> You can also simply use:
> 
> nDescend := StoD("96120207") - dDate
> 
> And the reverse would be:
> 
> dDate := StoD("96120207") - nDescend
> 
> And all xBase dialects have the StoD() and/or CtoD() functions.
> 
> Thanks, Luiz!
> 
> Hope that helps,
> 
> Andreas
> 
Hi Again,

Thanks for passing on Luiz's suggestion!!!

Works great.  If anyone is interested here is the "final" code in 
Xbase++ format that should easily convert to VFP:

FUNCTION uDescend(xVal)
LOCAL xDescend,;
       nAsc,;
       nPnt,;
       cValType

    cValType := VALTYPE(xVal)

    IF cValType == "C"
       xDescend := ""
       FOR nPnt := 1 TO LEN(xVal)

          nAsc := 256-ASC(SUBSTR(xVal,nPnt,1))
          *nAsc := 255-ASC(xVal[nPnt])
          xDescend += CHR(nAsc)

       NEXT nPnt
    ELSEIF cValType == "N"
       xDescend := -xVal
    ELSEIF cValType == "L"
       xDescend := ! xVal
    ELSEIF cValType == "D"
       *xDescend := 5231808 - DTOJ(xVal)       <--- works
       xDescend := STOD("96120207") - xVal     <--- works too!
    ENDIF

RETURN xDescend

Thanks to all who lent a hand... both in this news group and private 
email (Klaus)... This community is great!

Thanks again... Jonathan

jonathan.leeming@the-family-centre.com
Edmonton, Alberta, Canada

On 8/22/2019 5:53 AM, Andreas Gehrs-Pahl wrote:
> Jonathan,
> 
> The reason for the Spam Flag, is using that name of the programming language
> that is a synonym for Port or Haven. 
> 
> Your numbers are off by 30 days, though, at least as far as Xbase++ 2.0.1113
> is concerned.
> 
> The Descend calculation routine is quite simple:
> 
> 5231808 - DtoJ(Date()) is the same as Descend(Date())
> 
> The reverse is:
> 
> JtoD(5231808 - Descend(Date())
> 
> Using today's Date, 08/22/2019, we get the following:
> 
> dDate := CtoD('08/22/2019')
> ? Descend(dDate)        ==> 2773090
> ? 5231808 - DtoJ(dDate) ==> 2773090
> 
> ? DtoC(JtoD(5231808 - 2773090)) ==> 08/22/2019
> 
> The DtoJ() and JtoD() functions were added to Xbase++ with Version 2.00.832
> and don't exist in earlier versions.
> 
> In VFP, you have the functions SYS(10) -- String from Julian Day Number --
> and SYS(11) -- Julian Day Number from Date -- which might return the same
> values as Xbase++ does, but that would have to be tested.
> 
> Hope that helps,
> 
> Andreas
> 
Hi Andreas,

I thought that it was the reference to the Port / Haven however after 
the spam issue I tried a posting using the "forbidden word" in both the 
header & body to the test section and it worked fine!

I first tried your DTOJ() suggestion and it worked great... given the 
source not a surprise!

I was then anticipating the possibility of having to recreate my own 
DTOJ() function for use within VFP. (continued later in thread).

Thanks... Jonathan

jonathan.leeming@the-family-centre.com
Edmonton, Alberta, Canada