clock

(Not recommended; use datetime) Current date and time as date vector

clock is not recommended. To return the current date and time as a datetime value, use datetime instead. For more information on updating your code, see Version History or Replace Discouraged Instances of Serial Date Numbers and Date Strings.

Syntax

c = clock

[c tf] = clock

Description

c = clock returns a six-element date vector containing the current date and time in decimal form:

[year month day hour minute seconds]

The clock function calculates the current date and time from the system time.

[c tf] = clock returns a second output argument that is 1 (true) if the current date and time occur during daylight saving time (DST) in your system's time zone, and 0 (false) otherwise.

Examples

Round clock Output to Integer Display

To return the current date and time, use the clock function. Set the output format so that floating-point values display with up to five digits.

format shortg
c = clock

c = 1×6

         2024            9            5           14           30       44.829

The sixth element of the date vector output (seconds) is accurate to several digits beyond the decimal point.

To round to integer display format, use the fix function.

fix(c)

ans = 1×6

        2024           9           5          14          30          44

Determine If Current Time Occurs During DST

To determine if the current date and time occur during daylight saving time (DST), use the second output of the clock function. tf is 1 (true) if c occurs during DST, and 0 (false) otherwise.

format shortg
[c tf] = clock

c = 1×6

         2024            9            5           15            1       35.305

tf = logical
   1

Limitations

• MATLAB^® Online™ returns current Coordinated Universal Time (UTC) rather than local time.

Tips

• To time the duration of an event, use the timeit or tic and toc functions instead of clock and etime. The clock function is based on the system time, which can be adjusted periodically by the operating system, and thus might not be reliable in time comparison operations.

Extended Capabilities

C/C++ Code Generation

Generate C and C++ code using MATLAB® Coder™.

Usage notes and limitations:

• Code generation is not supported for clock with two output arguments.

Thread-Based Environment

Run code in the background using MATLAB® backgroundPool or accelerate code with Parallel Computing Toolbox™ ThreadPool.

This function fully supports thread-based environments. For more information, see Run MATLAB Functions in Thread-Based Environment.

Version History

Introduced before R2006a

R2022b: Not recommended

There are no plans to remove clock. However, the datetime function is recommended instead. The datetime data type provides flexible date and time formats, storage out to nanosecond precision, and properties to account for time zones and daylight saving time.

To return the current time as a datetime value, call datetime. You can call it without any input arguments, or with "now" as the input argument.

d = datetime
% or
d = datetime("now")

d = datetime
   15-Apr-2022 15:53:28

To return the current time as a date vector, split it apart using the datevec function.

d = datevec(datetime)