weekday function odd results

I am using the function weekday and I find that, for instance, on 19790531 and 19790601 are both Wednesdays according to the function. Not only is 19790531 a Thursday, two subsquent dates should not be assigned to the same weekday.

Can anyone shed some light on this?

ps:

I am simply doing:

[DayNumber,DayName] = weekday(19790531)

Answer 1

[Steven Lord]

That doesn't do what you think it does.

>> datestr(19790531)
ans =
18-Aug-4184

If you intended for that number to refer to May 31, 1979:

>> D = datetime(19790531, 'ConvertFrom', 'yyyymmdd')
D = 
  datetime
   31-May-1979 00:00:00

>> [DayNumber, DayName] = weekday(D)
DayNumber =
     5
DayName =
Thu