dayOfYear

Determine the day of the year.

Usage

var dayOfYear = require( '@stdlib/time/day-of-year' );

dayOfYear( [month[, day, year]] )

Returns the day of the year.

var num = dayOfYear();
// returns <number>

By default, the function returns the day of the year for the current date (according to local time). To determine the day of the year for a particular day, provide month, day, and year arguments.

var num = dayOfYear( 12, 31, 2016 );
// returns 366

num = dayOfYear( 12, 31, 2017 );
// returns 365

A month may be either a month's integer value, three letter abbreviation, or full name (case insensitive).

var num = dayOfYear( 12, 31, 2016 );
// returns 366

num = dayOfYear( 'dec', 31, 2016 );
// returns 366

num = dayOfYear( 'december', 31, 2016 );
// returns 366

The function also supports providing a Date object.

var num = dayOfYear( new Date() );
// returns <number>

Examples

var dayOfYear = require( '@stdlib/time/day-of-year' );

var v;
var i;

for ( i = 0; i < 2021; i++ ) {
    v = dayOfYear( 'Dec', 31, i );
    console.log( 'In the year %d, December 31 is day number %d.', i, v );
}

CLI

Usage

Usage: day-of-year [options] [<month> <day> <year>]

Options:

  -h,    --help                Print this message.
  -V,    --version             Print the package version.

Examples

$ day-of-year
<number>

For a specific date,

$ day-of-year 12 31 2016
366