Universal Time Code

Converts UTC from and to MATLAB datenum.

Description

These functions converts UTC to and from MATLAB datenum.

utc2date from UTC to datenum
date2utc from datenum to UTC.

On windows system the required timezone information is gathered from the registry.

• MATLAB release: MATLAB 6.5 (R13)
• Other requirements: Tested on windows XP and 2000 using Version 6.5 and 6/5.3 (The registry part have to be commented out)

[tony dinardo]

I get these errors when trying to use this -- it doesnt work:
Error in ==> C:\MATLAB6p1\toolbox\matlab\winfun\winqueryreg.dll
Error in ==> d:\mfiles\functions\date2utc.m
On line 20 ==> n=winqueryreg('name',rk,sk);

[Stephen Lawrence]

It doesn't look like this function handles Daylight Savings Time, so the UTC conversion is only valid for today's date.

[Rafael Palacios]

date2utc provides the number of seconds since 01Jan1900 at 00:00:00 UTC instead of the number of seconds sinde 01Jan1970 at 00:00:00 UTC.

[Jeff Burch]

I believe there is a problem with these as the base time for UTC should be 1970 and not 1904. This impacts the calculation of baseutc in both files:

current:
baseutc=datenum(1904,1,1,Timezone,0,0)*seconds_per_day;

recommended change:
baseutc=datenum(1970,1,1,Timezone,0,0)*seconds_per_day;