# [gantt] adding days to date / date arithmeric

Hi,
in a gantt-diagram, I need to add a sqeuence of 2-week sprints. Depicting the sprints serves as a reference for the other things that need to be planned in the diagram.

I would like to use a procedure to generate a number of sprints with a fixed length, much rather than inputing each activity with its dates by hand.

In order to be able to do so, I would need a function that allows me to add a given number of days to a starting date.

Afaik, this is not possible as of now.
commented Oct 7, 2021 by (68,340 points)

Hello C.,

Why not just use  '2 weeks' duration, like:

@startuml
[Sprint 1] lasts 2 weeks
then [Sprint 2] lasts 2 weeks
then [Sprint 3] lasts 2 weeks
then [Sprint 4] lasts 2 weeks
@enduml

or

@startuml
Project starts 2021-10-04
saturday are closed
sunday are closed
[Sprint 1] lasts 2 weeks
then [Sprint 2] lasts 2 weeks
then [Sprint 3] lasts 2 weeks
then [Sprint 4] lasts 2 weeks
@enduml

If that can help,
Regards,
Th.

commented Oct 12, 2021 by (120 points)
Hi Th.
at first I thought - "Great, this is it!", but unfortunately this approach collides with using holidays.

My sprints need to have a fixed 2-week duration and going with "lasts 2 weeks" will only use days which are not marked as holidays - thus making sprints longer when there's a holiay during the 2 weeks time.

@startuml
Project starts 2021-10-04
saturday are closed
sunday are closed

2021-10-26 is closed
2021-10-27 is closed
2021-10-28 is closed

[Sprint 1] lasts 2 weeks
then [Sprint 2] lasts 2 weeks
then [Sprint 3] lasts 2 weeks
then [Sprint 4] lasts 2 weeks
@enduml

Or is there a way to tell "lasts" for a certain activity to not respect holidays?

Apart from that, I am not keen on having the connection between the sprints which is introduced by the "then" syntax, but this is something I could live with.

Cheers,
Bastian

PS: Where can I find documentation on how to add code-examples properly?

answered Oct 22, 2021 by (295,000 points)

Maybe this is related to http://forum.plantuml.net/7781/gantt-chart-colorize-time-sections

commented Oct 22, 2021 by (68,340 points)

Hello all,

That is the same...

Compare:

@startgantt
Project starts 2021-10-04
saturday are closed
sunday are closed

2021-10-04 and 10 days are colored in lightblue and are named [Sprint 1]
then 10 days are colored in lightgreen and are named [Sprint 2]
then 10 days are colored in lightblue and are named [Sprint 3]
then 10 days are colored in lightgreen and are named [Sprint 4]
[Production] lasts 3 days and starts at [Sprint 3]'s start
then [Prod generalization] lasts 10 days

@endgantt

And:

@startgantt
Project starts 2021-10-04
saturday are closed
sunday are closed

2021-10-26 is closed
2021-10-27 is closed
2021-10-28 is closed

2021-10-04 and 10 days are colored in lightblue and are named [Sprint 1]
then 10 days are colored in lightgreen and are named [Sprint 2]
then 10 days are colored in lightblue and are named [Sprint 3]
then 10 days are colored in lightgreen and are named [Sprint 4]
[Production] lasts 3 days and starts at [Sprint 3]'s start
then [Prod generalization] lasts 10 days

@endgantt

Then...

Perhaps adding a new form, for example:

[Sprint 1] lasts 14 fixed days

to force duration without take care of closed days during the period....

Regards.