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How do I read this csv file in and convert the dates?

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T4H14
T4H14 2017-10-20
编辑： T4H14 2017-10-20
How can I use readtable() to read in this .csv and convert the dates from AM/PM to 24 hour at the same tieme
NA-KBOS , Hourly Forecast Made Oct 19 2017 1509 UTC
LocalTime, Temp, TempDiff, TempNormal, DewPoint, Cloud Cover, FeelsLikeTemp, FeelsLikeTempDiff, Precip, WindDir, WindSpeed(mph)
10/19/2017 12:00:00 AM,55.04,-2.1,48.75,46.94,0,55.04,-2.1,0,200,8.1,
10/19/2017 1:00:00 AM,53.96,-2.41,47.2,46.94,0,53.96,-2.41,0,180,8.1,
10/19/2017 2:00:00 AM,53.06,-2.66,46,46.94,0,53.06,-2.66,0,210,9.2,
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Walter Roberson
Walter Roberson 2017-10-20
Unfortunately, %D formats can only handle spaces in the case where the whitespace property has been set to exclude space.
Try
temp = datestr( datenum(B(:,1), 'mm/dd/yyyy HH:MM:SS PM'), 'mm/dd/yyyy HH:MM:SS');
B(:,1) = cellstr(temp);
T4H14
T4H14 2017-10-20
编辑：T4H14 2017-10-20
When I try that I get:
temp = datestr( datenum(B(:,1), 'mm/dd/yyyy HH:MM:SS PM'), 'mm/dd/yyyy HH:MM:SS');
Error using datenum (line 181) DATENUM failed.
Caused by: Error using datenum (line 109) The input to DATENUM was not an array of character vectors.

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Jeremy Hughes
Jeremy Hughes 2017-10-20
编辑：Jeremy Hughes 2017-10-20
Hi, I have two things.
The first is that readtable should recognize the format, and return datetimes (assuming you are in a recent release. I didn't need to pass anything in to get DATETIME out.) If not, then the format should be %{MM/dd/uuuu hh:mm:ss aa}D.
Second, the format you see is only a display format. You can simply change the format of the array to see it in 24 hour time.
This should be as easy as:
T = readtable(filename)
T.LocalTime.Format = 'MM/dd/uuuu HH:mm:ss'
Check out the datetime page for more info on the formats supported. https://www.mathworks.com/help/matlab/ref/datetime.html

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