I'm trying to convert date string to date number using dtstr2dtnummx (three time faster than datenum), but for this input
dtstr2dtnummx({'2010-12-12 12:21:13.101'},'yyyy-mm-dd HH:MM:SS.FFF')
and this input
dtstr2dtnummx({'2010-12-12 12:21:13.121'},'yyyy-mm-dd HH:MM:SS.FFF')
getting the same output. I used the 开发者_Python百科following tutorial to build up the date format.
Ahh sorry, UPDATED
The corresponding format of 'FFF' in datenum is 'SSS' in dtstr2dtnummx, as can be seen in cnv2icudf.m line #126. The end result is:
>> d1 = dtstr2dtnummx({'2010-12-12 12:21:13.101'},'yyyy-MM-dd HH:mm:ss.SSS')
d1 =
734484.514734965
>> d2 = dtstr2dtnummx({'2010-12-12 12:21:13.121'},'yyyy-MM-dd HH:mm:ss.SSS')
d2 =
734484.514735197
>> % double check the results - difference should equal 0.02 secs:
>> secsPerDay = 24*60*60;
>> timeDiff = secsPerDay * (d2-d1)
timeDiff =
0.019996
I have now posted an article about this on http://undocumentedmatlab.com/blog/datenum-performance/
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