date and time serial conversion

AA
2014 11 4
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更新时间：2014 11 5
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I have a table with one million rows and 5 columns. The first column has the dates and the second column the time. I want toconvert the date and time to a number as i want to turn the table into a matrix and a matrix cannot have date and time.

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James Tursa
James Tursa 2014-11-4
How is the data stored? Cell array of strings or what? What number do you want the date converted to? Datenum or Julian Day or what?
AA
AA 2014-11-4
the data is stored in table format (so not matrix or cell array but table format). I want to convert it to a matrix. The date is given as '26.07.2004' in column 1 and the time is given as '2:00' in column 2. I want the date to appear as 26072004 and the time as 0200. Then I can convert this table into a matrix.
per isakson
per isakson 2014-11-4
"appear as 26072004" &nbsp Why do you want it that way? To me that is asking for problems down the road.
AA
AA 2014-11-4
you are right. datenum format is better. How do I change it into datenum format?

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per isakson
per isakson 2014-11-4
编辑：per isakson 2014-11-5

1 个投票

Hint:
>> sdn = datenum('04.11.2014','dd.mm.yyyy' )
sdn =
735907
Matlabs serial date number and
>> [60,1]*sscanf( '12:48', '%2d:%2d')
ans =
768
minutes after midnight
A nice thing about this is that you get integers (flint) and do not need to worry about precision when you do comparisons.
&nbsp
Some code added
fid = fopen('AA.txt');
cac = textscan( fid, '%s%s%f' );
fclose(fid)
[60,1]*sscanf( transpose(char(cac{2})),'%2d:%2d', [2,inf] )
returns
ans =
767 768 769
where &nbsp AA.txt &nbsp contains
04.11.2014 12:47 1
04.11.2014 12:48 2
04.11.2014 12:49 3

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AA
AA 2014-11-4
how can i incorporate the table into the time command. x variable is the the column that has the values for time and i get the following error:
b=[60,1]*sscanf(x, '%2d:%2d') Error using sscanf First argument must be a string.
per isakson
per isakson 2014-11-4
编辑：per isakson 2014-11-4
"the table" &nbsp what do you mean by table? Do you mean a text-file?
"x" &nbsp what is x?

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更多回答（1 个）

Michael Haderlein
Michael Haderlein 2014-11-4

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You can use datenum:
datevec(datenum('04.11.2014 12:48','dd.mm.yyyy HH:MM'))
ans =
2014 11 4 12 48 0

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AA
AA 2014-11-4
I want the date to be converted to one integer and stay in the same column and row. the table variable is called x

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