how convert 13 digits of timestamp?

*hi,

how convert 13 digits of timestamp like 1238536800000 into small number with 6 digits It is easy to deal with it.

THANKS *

[Walter Roberson]

Please give us a sample timestamp and the exact time that it represents. Are the timestamps relative or absolute times? Are they possibly something like microseconds since a fixed time (as seen in MS Windows sometimes) ?

[nada ali]

like : datestr(730851) ans = 31-Dec-2000 currently, I need only date thanks

[Azzi Abdelmalek]

You have the date. What is the problem?

[Campion Loong]

Hi Nada,

If you have MATLAB 2014b or above, you can also use datetime to accomplish what you need. For example:

>> myDate = datetime(730851,'ConvertFrom','datenum')
myDate = 
   31-Dec-2000 00:00:00

Then you can conveniently extract various datetime components such as:

>> myYear = year(myDate)
myYear =
        2000

For more details please refer to documentation: Components of Dates and Time

[nada ali]

No I have no matlab 14, Aziz i have no date that is only example what I need is how convert 1238536800000 into date thanks

[Stephen23]

@nada ali: what epoch and increment does that timestamp have? Without knowing what time system or encoding this timestamp uses, your question is impossible to answer.

[nada ali]

thanks I just found the dataset with the following format including timestamp

*userID artistID tagID timestamp

2 52 13 1238536800000

2 52 15 1238536800000

2 52 18 1238536800000

2 52 21 1238536800000

2 52 41 1238536800000*

Answer 1

[Walter Roberson]

Divide the 13 digit timestamp by 1000 to get seconds. Divide by 24 * 60 * 60 to get days. Add datenum('1970-1-1'). The result will be a MATLAB date number.

This task would have been easier if you had identified the source of the data; I tracked it down by searching on the heading you provided and showed that it was an extract of last.fm data. After that it was a matter of researching to find out what timestamp format that last.fm used. When that was unsuccessful I took a sample timestamp from the last.fm site and googled it and was fortunate to find a discussion about Drupal in which someone was asking about proper conversion of the timestamp, and that gave me a target date to reverse-engineer from. The rest was based upon my historical knowledge of Unix timestamps starting at January 1 1970.

Answer 2

[Azzi Abdelmalek]

use

 format short

or

s=1238536800000  
fprintf('%6.6g\n',s)