now

Current date and time as serial date number

Syntax

t = now

Description

Note

The now function returns a serial date number that represents the current time. However, it is recommended that you use datetime values to represent points in time. To return the current time as a datetime value, use the datetime('now') syntax.

t = now returns the current date and time as a serial date number. A serial date number represents the whole and fractional number of days starting from a fixed, preset date (January 0, 0000).

Examples

Return and Convert Serial Date Numbers

Change the output display for numbers to long, fixed-decimal format. Then return the current date and time as a serial date number.

format longG
t = now

t = 
          738400.460972527

The whole part of t corresponds to the date, and the fractional part corresponds to the time of day. One way to show the date and time is to convert t using the datetime function.

d = datetime(t,'ConvertFrom','datenum')

d = datetime
   01-Sep-2021 11:03:48

To represent the date alone, without the time of day, use the floor function. Convert the result to a datetime value for display.

t2 = floor(t)

t2 = 
      738400

d2 = datetime(t2,'ConvertFrom','datenum')

d2 = datetime
   01-Sep-2021

Limitations

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

More About

January 0, 0000

Date specified to include a year 0 in the proleptic Gregorian calendar. For more information, see January 0 and Year zero.

Tips

• To represent the current date and time as a serial date number, as text, or as a datetime value, use the function calls shown in the table.

  Function Call	Output
  floor(now)	Current date as a serial date number
  rem(now,1)	Current time as a serial date number
  datestr(now)	Current date and time as text
  char(datetime('now'))
  string(datetime('now'))
  datetime('now')	Current date and time as a datetime value
  datetime(now,'ConvertFrom','datenum')

Extended Capabilities

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.