MATLAB Programming

2 Data Types
Date Strings
There are a number of different styles in which to express date and time
information as a date string. For example, several possibilities for October 31,
2003 at 3:45:17 in the afternoon are
31-Oct-2003 15:45:17
10/31/03
15:45:17
03:45:17 PM
If you are working with a small number of dates at the MATLAB command
line,thendatestringsareoftenthemostconvenientformattouse.
Note The MATLAB date function returns the current date as a string.
Serial Date Numbers
A serial date number represents a calendar date as the number of days that
has passed since a fixed base date. In MATLAB, serial date number 1 is
January 1, 0000. MATLAB also uses serial timetorepresentfractionsofdays
beginning at midnight; for example, 6 p.m. equals 0.75 serial days. So the
string ’31-Oct-2003, 6:00 pm’ in MATLAB is date number 731885.75.
MATLAB works internally with serial date numbers. If you are using
functions that handle large numbers of dates or doing extensive calculations
with dates, you get better performance if you use date numbers.
Note The MATLAB now function returns the current date and time as a
serial date number.
Date Vectors
Date vectors are an internal format for some MATLAB functions; you do not
typically use them in calculations. A date vector contains the elements [year
month day hour minute second].
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