2013

Table Of Contents

D System Variables

DATE

Stores the current date and time in Modified Julian Date format.

(Read-only)

RealType:

Not-savedSaved in:

VariesInitial value:

This value is represented as a Modified Julian Date (MJD), which is the Julian

day number and decimal fraction of a day in the format:

The Modified Julian Date, conventionally called UT1, is a worldwide scientific

standard that assigns day numbers beginning at an essentially arbitrary date

and time of 12:00 a.m. on 1 January 4713 B.C. (B.C.E.). With this system, 4

July 1997 at 2:29:58 p.m. corresponds to 2450634.60387736, and 1 January

1998 at 12:00 noon corresponds to 2450815.50000000.

You can compute differences in date and time by subtracting the numbers

returned by DATE. To extract the seconds since midnight from the value

returned by DATE, use AutoLISP expressions:

(setq s (getvar "DATE"))

(setq seconds (* 86400.0 (- s (fix s))))

Because your computer clock provides the date and time, the DATE system

variable returns a true Julian date only if the system clock is set to UTC/Zulu

(Greenwich Mean Time).

TDCREATE (page 1504) and TDUPDATE (page 1505) have

the same format as DATE, but their values represent the creation time and

last update time of the current drawing.