Ben Tupper <pemaquidriver@tidewater.net> wrote in message
news:3B017E66.BD5C9F6D@tidewater.net...
> Hello,
>
>
> 1) Unless the Julian Day Number is double precision, the
> minute and hour are always zero.
> 2) I don't believe the hour is correctly determing when
> the Julian Day number is provided as single precision.
> If the Julian Day begins at 1200 on a given day, then 0.36 *
> 24 + 12 = 20.6 (fraction of day * hours per day + offset =
> hour number of day)
I don't think it is a bug. Single precision numbers only give you
0.25 in terms of julian days
Check out the following code
print,'Singl prec #:'
print,float(2529161.36d),format='(f50.25)'
CALDAT,2529161.36d, Month, Day, Year, Hour, Minute,Second
PRINT, 'Doubl: ',Month, Day, Year, Hour, Minute, Second
CALDAT, 2529161.36, Month, Day, Year, Hour, Minute,Second
PRINT, 'Float: ',Month, Day, Year, Hour, Minute, Second
CALDAT, 2529161.25d, Month, Day, Year, Hour, Minute,Second
PRINT, 'Round Doub:',Month, Day, Year, Hour, Minute, Second
print,'Next Singl prec #:'
print,float(2529161.45d),format='(f50.25)'
CALDAT,2529161.45d, Month, Day, Year, Hour, Minute,Second
PRINT, 'Doubl: ',Month, Day, Year, Hour, Minute, Second
CALDAT, 2529161.45, Month, Day, Year, Hour, Minute,Second
PRINT, 'Float: ',Month, Day, Year, Hour, Minute, Second
CALDAT, 2529161.5d, Month, Day, Year, Hour, Minute,Second
PRINT, 'Round Doub:',Month, Day, Year, Hour, Minute, Second
;****************** Results Below *****************************************
Singl prec #:
2529161.2500000000000000000000000
Doubl: 7 4 2212 20
38 23.999989
Float: 7 4 2212 18
0 0.00000000
Round Doub: 7 4 2212 18 0
0.00000000
Next Singl prec #:
2529161.5000000000000000000000000
Doubl: 7 4 2212 22
48 1.6093257e-005
Float: 7 5 2212 0
0 0.00000000
Round Doub: 7 5 2212 0 0
0.00000000
Cheers,
bob stockwell
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