Convert datetime to numeric - preserve date format
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I have a timetable with dates (datetime data type) in the format 'yyyy-MM-dd HH:mm'. I want to convert these to a numeric data type (double) but keeping the exact numbers of each date such that the datetime '2023-02-27 14:00' is converted to the double '202302271400'. The function yyyymmdd() allows me to do this for the date, but not the hour and minute, and none of the other built in functions to convert to datenumber seem to have this option. Thanks for any insights to this problem.
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Edited to work with datetime array vs a single datetime.
d = datetime(['2023-02-27 14:00'; '2023-02-27 15:00']) % test data - replace with your timetable
s = string(d, 'yyyyMMddHHmm')
format long
% f = cellfun(@(s)sscanf(s, '%f'), s) % original method of converting to double
f = double(s) % An easier/cleaner method. Thanks to Walter for reminding me about this.
compose('%.0f', f)
10 个评论
Just use the 'Format' for this, then convert it to a string or char array in either the same line or a separate assignment —
d = datetime(['2023-02-27 14:00'; '2023-02-28 15:00'], 'Format','yyyyMMddHHmm')
ds = string(d)
dc = char(d)
.
Les Beckham
2023-2-27
I thought about that approach, but OP says that they already have the timetable. Who knows what format it was created with. Besides, they (for some unknown reason) wanted the result to be a float. Hence the sscanf call. I'll edit my answer to make it clear that the first line represents test data that will be replaced with the existing timetable.
Star Strider
2023-2-27
There are single quotes around the desired ‘double’ result, so there may be a bit of confusion on the OP’s part in that regard.
Les Beckham
2023-2-27
Good point. I saw that too, but they said "numeric type (double)".
Note that the compose command at the end was just to show that the values in f (the double result) are correct by printing them out -- since the exponential notation of the display of f makes it hard to tell if the decimal is in the right place.
Elin Jacobs
2023-2-27
Walter Roberson
2023-2-28
You should not need sscanf of string array: just double() the string array
Les Beckham
2023-2-28
Of course, thanks for reminding me of that. I've edited the answer to reflect this approach.
Campion Loong
2023-3-29
@Walter Indeed. The question is meant for @Elin Jacobs. I mistook @Les Beckham to be the OP. Let me restate:
@Elin Although you can turn datetime into 'formatted numbers' with any of the above answers, would you mind elaborating on what makes you do that in the first place? Are you interfacing with another system that needs numerics representation of time in some way (like a database)?
Elin Jacobs
2023-3-29
Campion Loong
2023-3-29
@Elin Jacobs Thanks for confirming. That (unfortunately) makes sense.
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