Filter löschen
Filter löschen

How to convert a datenum to a datetime?

588 Ansichten (letzte 30 Tage)
JFz
JFz am 17 Nov. 2017
Kommentiert: JFz am 20 Nov. 2017
Hi, I have table with column of datenum. I need to do a join with another table which has also a column of date but in just a plain format such as '11/1/2017'. But I got this error: Left and right key variables 'Date' and 'Date' are not comparable because one is a non-cell. How to resolve this error? Thanks a lot!

Akzeptierte Antwort

Star Strider
Star Strider am 17 Nov. 2017
Use the 'ConvertFrom' option:
t = datetime(X,'ConvertFrom','datenum')
  6 Kommentare
JFz
JFz am 17 Nov. 2017
Works. Thanks!
Star Strider
Star Strider am 17 Nov. 2017
My pleasure!

Melden Sie sich an, um zu kommentieren.

Weitere Antworten (1)

Peter Perkins
Peter Perkins am 20 Nov. 2017
Star Strider's answer seems like the long way around. JFz, it always helps to provide a short concrete example so people don't have to guess, but it sounds like you have one table with a datenum variable and another with a datestr variable,
>> t1 = table(floor(now) + [1;2;3],[1;2;3],'VariableNames',{'Date' 'X'})
t1 =
3×2 table
Date X
______ _
737020 1
737021 2
737022 3
>> t2 = table(datestr(floor(now) + [3;2;1]),[33;22;11],'VariableNames',{'Date' 'Y'})
t2 =
3×2 table
Date Y
___________ __
[1x11 char] 33
[1x11 char] 22
[1x11 char] 11
and you want to join the two tables using dates as the key. Convert the dates to datetimes, and you're done:
>> t1.Date = datetime(t1.Date,'ConvertFrom','datenum')
t1 =
3×2 table
Date X
____________________ _
21-Nov-2017 00:00:00 1
22-Nov-2017 00:00:00 2
23-Nov-2017 00:00:00 3
>> t2.Date = datetime(t2.Date)
t2 =
3×2 table
Date Y
___________ __
23-Nov-2017 33
22-Nov-2017 22
21-Nov-2017 11
>> t3 = join(t1,t2)
t3 =
3×3 table
Date X Y
____________________ _ __
21-Nov-2017 00:00:00 1 11
22-Nov-2017 00:00:00 2 22
23-Nov-2017 00:00:00 3 33
  1 Kommentar
JFz
JFz am 20 Nov. 2017
Yes! You are giving an excellent example. Thank you!

Melden Sie sich an, um zu kommentieren.

Kategorien

Mehr zu Dates and Time finden Sie in Help Center und File Exchange

Tags

Produkte

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by