MATLAB Function Reference
datenum

Serial date number

Syntax

• ```N = datenum(DT)
N = datenum(DT`,``P`)
N = datenum(Y,M,D)
N = datenum(Y,M,D,H,MI,S)
```

Description

The `datenum` function converts date strings and date vectors (defined by `datevec`) into serial date numbers. Date numbers are serial days elapsed from some reference date. By default, the serial day 1 corresponds to 1-Jan-0000.

```N = datenum(DT) ``` converts the date string or date vector `DT` into a serial date number. Date strings with two-character years, e.g., `12-june-12`, are assumed to lie within the 100-year period centered about the current year.

 Note    If `DT` is a string, it must be in one of the date formats `0`, `1`, `2`, `6`, `13`, `14`, `15`, 16, or `23` as defined by `datestr`.

```N = datenum(DT,P) ``` uses the specified pivot year as the starting year of the 100-year range in which a two-character year resides. The default pivot year is the current year minus 50 years.

```N = datenum(Y,M,D) ``` returns the serial date number for corresponding elements of the `Y`, `M`, and `D` (year, month, day) arrays. `Y`, `M`, and `D` must be arrays of the same size (or any can be a scalar). Values outside the normal range of each array are automatically "carried" to the next unit.

```N = datenum(Y,M,D,H,MI,S) ``` returns the serial date number for corresponding elements of the `Y`, `M`, `D`, `H`, `MI`, and `S` (year, month, day, hour, minute, and second) array values. `Y`, `M`, `D`, `H`, `MI`, and `S` must be arrays of the same size (or any can be a scalar). Values outside the normal range of each array are automatically carried to the next unit (for example month values greater than 12 are carried to years). Month values less than 1 are set to be 1. All other units can wrap and have valid negative values.

Examples

Convert a date string to a serial date number.

• ``````n = datenum('19-May-2001')
```
```n =
``````      730990
``````

Specifying year, month, and day, convert a date to a serial date number.

• ``````n = datenum(2001,12,19)
```
```n =
``````      731204
``````

Convert a date vector to a serial date number.

• ``````format bank
``````n = datenum([2001 5 19 18 0 0])
```
n =
730990.75
```

Convert a date string to a serial date number using the default pivot year

• ```n = datenum('12-june-12')

n =
735032
```

Convert the same date string to a serial date number using 1900 as the pivot year.

• ```n = datenum('12-june-12', 1900)

n =
698507
```

`datestr`, `datevec`, `now`

 date datestr