wiki/notebook/text.org-mode.timestamps.org

:PROPERTIES:
:ID:       3a57fe56-9e6d-41e4-a76f-5ffdeb5840a2
:END:
#+title: Org mode timestamps
#+date: "2020-04-21 19:44:15 +08:00"
#+date_modified: "2021-05-04 20:52:15 +08:00"
#+language: en
#+property: header-args:org  :results silent
#+tags: personal-info-management


As previously stated, [[id:c422175a-5b65-4311-8cc6-11efd55364e8][Org mode]] is first created as an outliner enabling you to manage tasks.
Here's some of the features you might be interested when using it as such.




* Timestamps and durations

Being a personal information tool, Org mode heavily features timestamps.

#+begin_src org
<2021-04-21 Wed>
#+end_src

You can easily set a timestamp with ~org-time-stamp~ that comes with an interactive calendar and a prompt to indicate the date and time.
The [[https://orgmode.org/manual/The-date_002ftime-prompt.html][prompt]] is more useful since you can quickly enter relative values such as:

- =+1d= for tomorrow.
- =2020-05-01 +23d= means 23 days after the 2020-05-01.
- =+4d 10:00+2= for 4 days later starting from 10:00 to 12:00.
- =+1m 1pm+3= for a month later starting from 1:00 PM to 4:00 PM.

Durations are made by putting a pair of dashes between two timestamps.

#+begin_src org
<2021-04-22 Thu>--<2021-04-25 Sun>
#+end_src

You can quickly create a duration by running ~org-time-stamp~ two times consecutively.




* Deadlines and schedules

In Org mode agenda view, it can show deadlines and schedules by prepending the timestamps with =DEADLINE= and =SCHEDULED=, respectively.

#+begin_src org
DEADLINE: <2021-04-26 Mon 22:00>
SCHEDULED: <2021-04-25 Sun 20:00>
#+end_src

- Deadline entries make up the tasks that has to be done by the specified datetime.
  When present in the agenda, it will warn an issue when the task is not done after the deadline had passed.

- Scheduled entries indicate the tasks that you will do starting from the timestamp.
  When present in the agenda, it will simply remind you to do the task until done.




* Repeated tasks

One can set [[https://orgmode.org/manual/Repeated-tasks.html][repeated tasks]] in the following format.

#+begin_src org
SCHEDULED: <2020-06-22 Mon +2d>
#+end_src

Any missed session will cause the agenda to keep overdued sessions and accumulate to repeat the tasks 'X' number of times with the number of overdued sessions.

Some tasks does not work this way, however.
You don't need to replace the batteries 5 times or brush your teeth 10 times to make up for it.
For this, you can do the following.

#+begin_src org
SCHEDULED: <2020-06-22 Mon ++2d>
#+end_src

One cool thing about it if you mark a task as done, it will simply create an entry of the task completed and update the base date.

#+begin_src org
,* TODO Watch the lectures from Brian Harvey's SICP series (https://archive.org/details/ucberkeley-webcast-PL3E89002AA9B9879E?sort=titleSorter)
SCHEDULED: <2020-06-24 Wed .+2d>
:PROPERTIES:
:LAST_REPEAT: [2020-06-22 Mon 22:01]
:END:
- State "DONE"       from "TODO"       [2020-06-22 Mon 22:01]
#+end_src