Incorrect Julian Day

[Pswin]

The following code produces wrong Julian day:

qDebug() << QDate( 622, 7, 16 ) ;

I would expect the results to be:
1948440 or 1948439.5

Instead i get:
1948437

you can check the correct Julian date from following websites:

http://numerical.recipes/julian.html
http://aa.usno.navy.mil/data/docs/JulianDate.php

Is it a bug? and should I report it?

[kshegunov]

@Pswin
Why do you assume you should get a Julian calendar date? The class may use that internally, but still the most widely used calendar nowadays is the Gregorian ... also there's this: QDate::toJulianDay

[micland]

Your using the gregorian calender as input, not the julian calender.
There is a gap of three days (see http://www.wolframalpha.com/input/?i=julian+date+622-7-16)

[Pswin]

@kshegunov
I am using it for converting between different calendars. actually I am writing an open source library for Qt which supports some calendars such as Persian and Hijri.

@micland
Thank you.

[kshegunov]

@Pswin
My point was that whatsoever the internal representation is the API still uses Gregorian calendar (which @micland stated explicitly).